Samacheer Kalvi Class 11 Bio Zoology Solutions Chapter 11 Chemical Coordination and Integration

Part I

 

Question 1. The maintenance of a constant internal environment is referred as
(a) Regulation
(b) homeostasis
(c) Co-ordination
(d) hormonal control
Answer: (b) homeostasis
In simple words: Homeostasis is how our body keeps everything inside stable and balanced, like keeping our temperature just right. This constant state helps all our body systems work properly.

🎯 Exam Tip: Remember that "homeostasis" refers to the body's internal stability, while "regulation" is a broader term for controlling any process.

 

Question 2. Which of the following are exclusive endocrine glands?
(a) Thymus and testis
(b) adrenal and ovary
(c) parathyroid and adrenal
(d) pancreas and parathyroid
Answer: (c) parathyroid and adrenal
In simple words: Exclusive endocrine glands only make and release hormones directly into the blood, without using ducts. The parathyroid and adrenal glands are good examples of this.

🎯 Exam Tip: Distinguish between exclusive endocrine glands (like parathyroid and adrenal) and mixed glands (like the pancreas, which has both endocrine and exocrine functions).

 

Question 3. Which of the following hormone is not secreted under the influence of the pituitary gland?
(a) thyroxine
(b) insulin
(c) oestrogen
(d) glucocorticoids
Answer: (b) insulin
In simple words: Insulin is a hormone that controls blood sugar and is made by the pancreas, not the pituitary gland. The pituitary gland is often called the 'master gland' because it controls many other glands, but not all of them.

🎯 Exam Tip: Understand which hormones are directly regulated by the pituitary gland and which operate independently or under different control mechanisms.

 

Question 4. Spermatogenesis in mammalian testes is controlled by
(a) Luteinising hormone
(b) Follicle-stimulating Hormone
(c) FSH and prolactin
(d) GH and prolactin
Answer: (b) Follicle-stimulating Hormone
In simple words: Follicle-stimulating hormone, or FSH, is key for making sperm in male animals. It tells the testes to start and continue the process.

🎯 Exam Tip: Remember that FSH is vital for gamete production in both males (spermatogenesis) and females (follicle development).

 

Question 5. Serum calcium level is regulated by
(a) Thyroxine
(b) FSH
(c) Pancreas
(d) Thyroid and parathyroid
Answer: (d) Thyroid and parathyroid
In simple words: Both the thyroid and parathyroid glands work together to keep the calcium levels in your blood just right. The thyroid produces calcitonin, and the parathyroid produces parathyroid hormone, which have opposite effects on calcium.

🎯 Exam Tip: Know the specific roles of calcitonin (from thyroid) and parathormone (from parathyroid) in calcium homeostasis.

 

Question 6. Iodised salt is essential to prevent
(a) rickets
(b) scurvy
(c) goiter
(d) acromegaly
Answer: (c) goiter
In simple words: Eating iodised salt helps stop a condition called goiter, where the thyroid gland gets big. Iodine is needed for the thyroid gland to work well.

🎯 Exam Tip: Understand that goiter is primarily caused by iodine deficiency, leading to an enlarged thyroid gland.

 

Question 7. Which of the following gland is related to immunity?
(a) Pineal gland
(b) adrenal gland
(c) thymus
(d) parathyroid gland
Answer: (c) thymus
In simple words: The thymus gland is very important for our body's defense system, helping immune cells called T-lymphocytes grow and learn. It plays a big role in childhood immunity.

🎯 Exam Tip: The thymus is crucial for the development and maturation of T-lymphocytes, which are central to cell-mediated immunity.

 

Question 8. Which of the following statement about sex hormones is correct?
(a) Testosterone is produced by Leydig cells under the influence of the luteinizing hormone
(b) Progesterone is secreted by corpus luteum and softens pelvic ligaments during childbirth
(c) Oestrogen is secreted by both sertoli cells and corpus luteum
(d) Progesterone produced by corpus luteum is biologically different from the one produced by the placenta.
Answer: (a) Testosterone is produced by Leydig cells under the influence of luteinizing hormone
In simple words: In males, Leydig cells in the testes make testosterone, and this process is controlled by luteinizing hormone (LH) from the pituitary gland. Testosterone is the main male sex hormone.

🎯 Exam Tip: Remember the specific cells and hormones involved in the regulation of male sex hormone production, particularly Leydig cells and LH.

 

Question 9. Hypersecretion of GH in children leads to
(a) Cretinism
(b) Gigantism
(c) Graves disease
(d) Tetany
Answer: (b) Gigantism
In simple words: When children make too much growth hormone, they can grow very tall, a condition called gigantism. This excessive growth happens because their growth plates are still open.

🎯 Exam Tip: Distinguish between gigantism (excess GH in children) and acromegaly (excess GH in adults), and their respective symptoms.

 

Question 10. A pregnant female delivers a baby who suffers from stunted growth, mental retardation, low intelligence quotient, and abnormal skin. This is the result of
(a) Low secretion of growth hormone
(b) Cancer of the thyroid gland
(c) Over secretion of pars distalis
(d) Deficiency of iodine in the diet
Answer: (d) Deficiency of iodine in the diet
In simple words: When a pregnant mother does not get enough iodine, her baby can be born with serious problems like stunted growth and brain development issues. Iodine is crucial for thyroid hormone production, which is vital for normal growth and development.

🎯 Exam Tip: Understand the critical role of iodine during pregnancy for fetal development and the severe consequences of its deficiency.

 

Question 11. The structure which connects the hypothalamus with the anterior lobe of the pituitary gland is the
(a) Dendrites of the neurohypophysis
(b) Axons of neuro hypophysis
(c) Bands of white fibers from the cerebellar region
(d) Hypophysial portal system
Answer: (d) Hypophysial portal system
In simple words: The hypophysial portal system is like a special blood vessel network that carries hormones from the hypothalamus directly to the front part of the pituitary gland. This connection allows the hypothalamus to control the pituitary very quickly.

🎯 Exam Tip: Focus on the direct vascular connection (portal system) between the hypothalamus and the anterior pituitary, which is key for endocrine regulation.

 

Question 12. Comment on homeostasis.
Answer: Homeostasis is how the body keeps its internal environment stable and constant. Different systems like the endocrine and nervous systems work together to achieve this balance. For example, if your body temperature rises, your nervous system signals sweat glands to cool you down, bringing the temperature back to normal. The endocrine system also plays a role, for instance, by regulating blood calcium levels through hormones from the parathyroid and thyroid glands, ensuring the body maintains the right balance. Both systems are vital for maintaining the body's stable internal state.
In simple words: Homeostasis means keeping everything inside your body balanced, like temperature and sugar levels. Both your nerves and your hormones work together to make sure this balance stays steady.

🎯 Exam Tip: When explaining homeostasis, always mention the involvement of both the nervous and endocrine systems and provide a clear example of how balance is maintained.

 

Question 13. Which one of the following statement is correct
(a) Calcitonin and thymosin are thyroid hormones
(b) Pepsin and prolactin are secreted in the stomach
(c) Secretin and rhodopsin are polypeptide hormones
(d) Cortisol and aldosterone are steroid hormones
Answer: (d) Cortisol and aldosterone are steroid hormones
In simple words: Cortisol and aldosterone are hormones made from cholesterol in the adrenal glands, which means they are steroid hormones. They help control things like stress and salt balance in the body.

🎯 Exam Tip: Remember that steroid hormones are lipid-soluble and derived from cholesterol, allowing them to pass through cell membranes easily.

 

Question 14. Which of the given option shows all wrong statements for thyroid gland Statements?
(i) It inhibits the process of RBC formation
(ii) It helps in the maintenance of water and electrolytes
(iii) It's more secretion can reduce blood pressure
(iv) It stimulates osteoblast
(a) (i) and (ii)
(b) (iii) and (iv)
(c) (i) and (iv)
(d) (i) and (iii)
Answer: (d) (i) and (iii)
In simple words: The thyroid gland actually helps make red blood cells and too much thyroid hormone can increase blood pressure, not reduce it. So, statements (i) and (iii) are incorrect about the thyroid gland's actions.

🎯 Exam Tip: For "wrong statement" questions, carefully evaluate each sub-statement based on your knowledge of the organ's normal functions before selecting the option.

 

Question 15. Hormones are known as a chemical messengers. Justify.
Answer: Hormones are like special chemical signals released into the blood. They travel through the bloodstream and act specifically on certain organs or tissues, called target organs. They either speed up, slow down, or change what these target tissues do. Because they carry messages and cause changes in specific parts of the body, they are called chemical messengers. For instance, insulin carries a message to cells to absorb glucose from the blood.
In simple words: Hormones are like tiny messages sent through your blood that tell specific body parts what to do. They help control how your body works by sending these chemical instructions.

🎯 Exam Tip: Emphasize that hormones are chemical signals, travel through the bloodstream, and act on specific target cells or organs to justify their role as "chemical messengers."

 

Question 16. Write the role of t-oestrogen in ovulation.
Answer: Oestrogen hormones help the ovarian follicle to grow inside the ovary. As these follicles grow, they secrete more oestrogen. This oestrogen then helps the ovum (egg cell) to develop properly. When oestrogen levels reach a certain peak, it triggers a surge in luteinizing hormone (LH), which causes the mature egg to be released from the ovary, a process called ovulation. High oestrogen levels are necessary to prepare the uterus for a possible pregnancy.
In simple words: Oestrogen helps an egg grow inside the ovary. When there's enough oestrogen, it tells the body to release the egg, which is called ovulation.

🎯 Exam Tip: Connect oestrogen's role in follicle growth and its crucial peak level that triggers the LH surge, leading to ovulation.

 

Question 17. Comment on Acini of the thyroid gland.
Answer: The thyroid gland, which is an endocrine gland, has two lobes. Each lobe is made up of many small sections called lobules. These lobules contain tiny sacs known as follicles or acini. Each acinus is lined with special cells that can be glandular, cuboidal, or squamous. The middle part, or lumen, of each acinus is filled with a thick jelly-like substance called colloid. This colloid contains thyroglobulin molecules, which are used to make thyroid hormones like Tri-iodothyronine (T3) and Thyroxine (T4). These hormones are important for metabolism.
In simple words: Acini are small sacs inside the thyroid gland. They are filled with a special substance that helps make thyroid hormones, which control how our body uses energy.

🎯 Exam Tip: Describe acini as the functional units of the thyroid, highlighting their cellular lining and the colloid within, where thyroid hormones are stored and synthesized.

 

Question 18. Write the causes for diabetes mellitus and diabetes insipidus.
Answer:
• Diabetes Mellitus: This happens when the pancreas does not produce enough insulin, or the body cannot use the insulin it makes well. Insulin's job is to help the liver and muscles turn glucose into glycogen for storage. If there isn't enough effective insulin, too much glucose stays in the blood, leading to high blood sugar levels. This is the more common type of diabetes.
• Diabetes Insipidus: This is a different condition caused by a problem with antidiuretic hormone (ADH), which is made by the neurohypophysis. ADH normally helps the kidneys reabsorb water, so the body doesn't lose too much through urine. If there is not enough ADH, the kidneys cannot save water, and the person produces large amounts of very dilute urine, leading to extreme thirst. These two types of diabetes affect different hormones and body functions.
In simple words: Diabetes mellitus is caused by not enough insulin or problems using it, leading to high blood sugar. Diabetes insipidus is caused by not enough ADH hormone, which makes people urinate too much water.

🎯 Exam Tip: Clearly differentiate between the two types of diabetes by identifying the specific hormone (insulin for mellitus, ADH for insipidus) and the primary physiological dysfunction for each.

 

Question 19. Specify the symptoms of acromegaly.
Answer: Acromegaly happens in adults when the body produces too much growth hormone (GH) after puberty, when growth plates have already closed. The main symptoms are an overgrowth of bones in the hands, feet, and jaw, making them larger than normal. People with acromegaly may also experience problems with their gonads, and their internal organs like the tongue, lungs, heart, liver, and spleen can become enlarged. Even other endocrine glands, such as the thyroid and adrenal glands, can show changes. This condition differs from gigantism, which occurs in children.
In simple words: Acromegaly makes adult bones, especially in the hands, feet, and jaw, grow too big due to too much growth hormone. It can also make organs get larger.

🎯 Exam Tip: List the key physical changes in bone structure (hands, feet, jaw) and internal organ enlargement as primary symptoms of acromegaly.

 

Question 20. Write the symptoms of cretinism.
Answer: Cretinism is a condition caused by a severe lack of thyroid hormones (hypothyroidism) during childhood. Children with cretinism show slow skeletal growth, meaning they are shorter than usual. They also have delayed sexual maturity and may have problems with their mental ability. Their skin can be thick and wrinkled, with a bloated face, and their tongue might be enlarged and protrude. Other signs include a slow heart rate, lower-than-normal body temperature, and high cholesterol levels in the blood. Early diagnosis and treatment are crucial to prevent severe developmental delays.
In simple words: Cretinism happens when children don't have enough thyroid hormone. Symptoms include slow growth, low intelligence, thick skin, a large tongue, and a slow heartbeat.

🎯 Exam Tip: When describing cretinism, focus on the developmental and physical symptoms resulting from hypothyroidism in children.

 

Question 21. Briefly explain the structure of the thyroid gland.
Answer: The thyroid gland is shaped like a butterfly and has two lobes. It is located in the neck, just below the voice box (larynx), on each side of the upper windpipe (trachea). A thin band of tissue called the isthmus connects the two lobes in the middle. Each lobe is made up of many small sections called lobules. Inside these lobules are tiny, round structures known as follicles or acini. Each acinus is lined by special glandular cells, which can be cuboidal or squamous. The central space of an acinus is filled with colloid, a thick fluid containing thyroglobulin molecules. The thyroid gland produces thyroid hormones (T3 and T4) from this thyroglobulin, which are important for regulating the body's metabolism and growth.
In simple words: The thyroid gland is a butterfly-shaped organ in the neck with two parts connected by a bridge. It is made of tiny sacs called acini, which store a special fluid to make hormones for our body's metabolism.

🎯 Exam Tip: Highlight the key features: butterfly shape, bilobed structure connected by isthmus, and the functional units (follicles/acini) filled with colloid for hormone storage and synthesis.

 

Question 22. Name the layers of adrenal cortex and mention their secretions.
Answer: The adrenal cortex has three main layers, each making different hormones:
• Zona Glomerulosa: This is the outermost layer and makes up about 15% of the cortex. It secretes mineralocorticoids, like aldosterone. Aldosterone helps control water and salt balance in the body.
• Zona Fasciculata: This is the middle and widest layer, making up about 75% of the cortex. It produces glucocorticoids, such as cortisol and corticosterone, and small amounts of adrenal androgens and oestrogen. Cortisol helps the body respond to stress and regulates metabolism.
• Zona Reticulata: This is the innermost layer, forming about 10% of the cortex (the source says 19%, but 10% is typical). It secretes adrenal androgens (male sex hormones) and small amounts of oestrogen and glucocorticoids. These hormones contribute to secondary sexual characteristics.
In simple words: The adrenal cortex has three layers, each making different hormones. The outer layer makes minerals, the middle layer makes stress hormones, and the inner layer makes sex hormones.

🎯 Exam Tip: Remember the three distinct layers of the adrenal cortex (Zona Glomerulosa, Fasciculata, Reticulata) and the primary type of hormone secreted by each, especially mineralocorticoids, glucocorticoids, and androgens.

 

Question 23. Differentiate hyperglycemia from hypoglycemia.
Answer: Hyperglycemia and hypoglycemia are two conditions related to blood glucose (sugar) levels, but they are opposite:
• Hyperglycemia: This is when there is too much glucose in the blood. It often happens when the body does not make enough insulin or cannot use insulin effectively. High blood sugar levels for a long time can damage organs. Eating too many sugary foods without proper insulin action can lead to this.
• Hypoglycemia: This is when there is too little glucose in the blood. It can be caused by producing too much insulin, which removes too much sugar from the blood. Low blood sugar can cause symptoms like dizziness and weakness. Sometimes, taking too much diabetes medication can cause hypoglycemia. Knowing the difference is crucial for managing blood sugar conditions.
In simple words: Hyperglycemia means your blood sugar is too high, usually from a lack of insulin. Hypoglycemia means your blood sugar is too low, often from too much insulin.

🎯 Exam Tip: Define each term clearly by its glucose level (high vs. low) and connect it to the corresponding insulin action (reduced secretion/ineffectiveness vs. increased secretion).

 

Question 24. Write the functions of (CCK)- Cholecystokinin.
Answer: Cholecystokinin (CCK) is a hormone released by the duodenum, the first part of the small intestine. It is secreted when fat and acid are present in the food that enters the duodenum. CCK has two main jobs: first, it tells the gallbladder to release bile, which helps break down fats. Second, it stimulates the pancreas to secrete digestive enzymes, which are then discharged into the duodenum to help digest carbohydrates, proteins, and fats. These actions ensure proper digestion of food in the small intestine.
In simple words: Cholecystokinin, or CCK, is a hormone that helps digest fats by making the gallbladder release bile and telling the pancreas to send out digestive juices.

🎯 Exam Tip: Remember that CCK is triggered by fat and acid in the duodenum and its key functions are bile release (gallbladder) and enzyme secretion (pancreas) for digestion.

 

Question 25. Growth hormone is important for normal growth. Justify the statement.
Answer: Growth hormone (GH) is indeed very important for normal growth because it affects almost all tissues and metabolic processes in the body. It helps in several ways:
• It affects how the body uses carbohydrates, proteins, and lipids, ensuring energy is available for growth.
• It increases the making of new proteins, which are the building blocks for all cells.
• It stimulates cartilage formation, which is crucial for bone growth.
• It encourages osteogenesis, the process of new bone formation.
• It helps the body keep important minerals like nitrogen, potassium, and sodium, which are vital for healthy development.
• It also helps release fatty acids from fat tissue and reduces how much glucose cells use for energy, saving glucose for important tissues like the brain. All these actions ensure the body grows properly and healthily.
In simple words: Growth hormone helps our bodies grow by influencing how we use food for energy, building new proteins and bones, and keeping important minerals. It makes sure all parts of our body grow correctly.

🎯 Exam Tip: When justifying the importance of growth hormone, list its key effects on metabolism (carbohydrates, proteins, lipids), tissue growth (cartilage, bone), and mineral retention.

 

Question 26. Pineal gland is an endocrine gland, write its role.
Answer: The pineal gland is a small endocrine gland, also called the epiphysis cerebri or conarium, located deep inside the brain, behind the third ventricle. It is made of special cells called parenchymal cells and interstitial cells. This gland's main job is to secrete the hormone melatonin. Melatonin plays a central role in controlling the body's circadian rhythm, which is our natural sleep-wake cycle. It also helps regulate when sexual maturity begins, and it influences metabolism, how our skin gets its color (pigmentation), the menstrual cycle in females, and the body's defense system. For instance, more melatonin is released in the dark, signaling the body to sleep.
In simple words: The pineal gland makes melatonin, a hormone that controls our sleep-wake cycle. It also helps with growth, skin color, and our body's defense system.

🎯 Exam Tip: Focus on melatonin as the primary hormone of the pineal gland and its crucial role in regulating circadian rhythms and sleep patterns.

 

Question 27. Comment on the functions of adrenalin.
Answer: Adrenalin, also known as epinephrine, is a hormone released by the adrenal glands, especially during stressful or emergency situations. It prepares the body for a "fight or flight" response through several key functions:
• It helps the liver break down stored glycogen into glucose and increases the release of fatty acids from fat cells, providing quick energy to the body.
• During emergencies, adrenalin rapidly increases the heart rate and blood pressure, pushing more blood to important organs.
• It makes the smooth muscles in the skin and internal organs' blood vessels tighten, which can reduce blood flow to less critical areas.
• It increases blood flow to the skeletal muscles, cardiac muscles, and nervous tissues, boosting their metabolic rate to enhance strength and quick reactions. This immediate energy boost is vital for responding to danger.
In simple words: Adrenalin is a hormone that gets your body ready for danger by speeding up your heart, raising blood pressure, and giving you more energy very quickly.

🎯 Exam Tip: Remember adrenalin's role in the "fight or flight" response, specifically its effects on heart rate, blood pressure, blood glucose, and blood flow to muscles.

 

Question 28. Predict the effects of removal of Pancreas from the human body.
Answer: The pancreas is a unique gland that acts as both an exocrine and an endocrine gland. It sits just below the stomach and looks like a leaf. If the pancreas were removed from the human body, it would have serious consequences:
• Digestive Problems: The pancreas produces important digestive enzymes (like amylase, lipase, and proteases) that break down carbohydrates, proteins, and fats in food. Without these enzymes, a person would not be able to digest food properly, leading to severe nutritional deficiencies and indigestion.
• Blood Sugar Regulation Issues: The pancreas also secretes hormones like insulin and glucagon, which are crucial for regulating blood sugar levels. Insulin lowers blood sugar, while glucagon raises it. Without the pancreas, the body would lose its ability to control blood sugar, leading to very high glucose levels (diabetes mellitus) or very low levels, making it impossible to maintain stable blood sugar. This would require lifelong insulin injections and careful diet management.
In simple words: If the pancreas is removed, a person cannot digest food or control their blood sugar. This is because the pancreas makes both digestive juices and hormones like insulin and glucagon.

🎯 Exam Tip: When discussing pancreatic removal, always mention both its exocrine (digestive enzymes) and endocrine (insulin, glucagon) functions and the resulting severe impact on digestion and blood sugar control.

 

Question 29. Enumerate the role of kidney as an endocrine gland.
Answer: The kidney is considered a partial endocrine gland because it produces and secretes several hormones that have important functions in the body:
• Renin: This hormone is secreted by the juxtaglomerular cells (JGA) in the kidney. Renin helps to increase blood pressure by starting a process that forms angiotensin, which tightens blood vessels.
• Erythropoietin: Also secreted by JGA cells, erythropoietin is vital for the formation of red blood cells (RBCs) in the bone marrow. This process is called erythropoiesis. When oxygen levels in the blood are low, the kidneys release erythropoietin to stimulate more RBC production.
• Calcitriol: This is the active form of vitamin D3, which the kidneys produce from a precursor. Calcitriol plays a key role in promoting the absorption of calcium and phosphorus from the small intestine, and it helps accelerate bone formation. This ensures healthy bones and proper mineral balance.
In simple words: Kidneys act like glands by making hormones such as renin, which raises blood pressure; erythropoietin, which helps make red blood cells; and calcitriol, which helps our body use calcium.

🎯 Exam Tip: List the three major hormones produced by the kidney (renin, erythropoietin, calcitriol) and briefly state the primary function of each to demonstrate its endocrine role.

I. Choose The Correct Answer

 

Question 1. Where is hormones released ifito?
(a) Mouth
(b) Blood
(c) Digestive system
(d) Kidney
Answer: (b) Blood
In simple words: Hormones are special chemicals released directly into the blood. The blood then carries them all around the body to where they need to act.

🎯 Exam Tip: Remember that endocrine glands release hormones directly into the bloodstream, distinguishing them from exocrine glands that use ducts.

 

Question 2. Find out the endocrine glands from the following.
(a) Sebaceous gland
(b) Sweat glands
(c) Salivary glands
(d) Thyroid gland
Answer: (d) Thyroid gland
In simple words: The thyroid gland is an endocrine gland because it produces hormones and releases them straight into the blood, without any tubes or ducts. Other glands listed use ducts to release their products.

🎯 Exam Tip: To identify endocrine glands, look for those that secrete hormones directly into the bloodstream, as opposed to exocrine glands which release substances through ducts.

 

Question 3. Which is called as master endocrine glands?
(a) Hypothalamus
(b) Pituitary gland
(c) Thyroid gland
(d) Thymus
Answer: (b) Pituitary gland
In simple words: The pituitary gland is called the "master gland" because it controls many other endocrine glands in the body by releasing its own hormones. It acts like a conductor for the body's hormone orchestra.

🎯 Exam Tip: The pituitary gland's "master" title comes from its regulatory influence over numerous other endocrine glands, although it is itself regulated by the hypothalamus.

 

Question 4. Where is pituitary situated?
(a) On the ethmoid bone
(b) On sella turcica
(c) On the foramen of Monro
(d) On the Rathkes packet
Answer: (b) On sella turcica
In simple words: The pituitary gland is located in a special bony hollow in the skull called the sella turcica. This protects the gland, which is vital for many body functions.

🎯 Exam Tip: Memorize the anatomical location of key glands, as their position often relates to their protective structures and functional connections.

 

Question 5. Serum calcium level is regulated by
(a) Thyroxine
(b) FSH
(c) Pancreas
(d) Thyroid and parathyroid
Answer: (d) Thyroid and parathyroid
In simple words: The thyroid and parathyroid glands work together to keep the right amount of calcium in your blood. They release special hormones that either add calcium to your blood or take it away, making sure the levels stay balanced.

🎯 Exam Tip: Remember that calcitonin from the thyroid lowers calcium, while parathormone from parathyroid raises it. This opposing action is key.

 

Question 6. Iodised salt is essential to prevent
(a) rickets
(b) scurvy
(c) goiter
(d) acromegaly
Answer: (c) goiter
In simple words: Eating iodised salt helps your body get enough iodine. This iodine is very important for your thyroid gland to work correctly, preventing a condition called goiter where the thyroid gland gets big.

🎯 Exam Tip: Highlight the direct link between iodine deficiency and thyroid issues, especially goiter, as a common exam point.

 

Question 7. A male child is born to a parents as he grown if FSH and LH is not properly secreted what happens to the male child.
(a) He grows as a normal male child
(b) He grows and he shows stunted growth
(c) Secondary sexual characters are not developed properly
(d) He grows as a mentally depressed male
Answer: (c) Secondary sexual characters are not developed properly
In simple words: FSH and LH are hormones that help with puberty. If a male child doesn't have enough of these, his body won't develop the usual adult male features like a deeper voice or body hair. This is because these hormones control the production of sex hormones like testosterone.

🎯 Exam Tip: Focus on FSH and LH as key hormones for sexual development in both males and females; their deficiency leads to a lack of secondary sexual characteristics.

 

Question 8. These hormones are collectively known as Gonodotropins?
(a) Oxytocin and ADH
(b) Oestrogen and Progestron
(c) Testosteron and androgens
(d) FSH and LH
Answer: (d) FSH and LH
In simple words: FSH (Follicle-Stimulating Hormone) and LH (Luteinizing Hormone) are grouped together as gonadotropins. They are called this because they act on the gonads (testes in males, ovaries in females) to control reproduction.

🎯 Exam Tip: Clearly define gonadotropins as hormones acting on gonads, and always associate FSH and LH with this term.

 

Question 9. The day and night rhythm is controlled by this hormone.
(a) Melonocytes
(b) Melanin
(c) Melotonin
(d) Thyroxine
Answer: (c) Melotonin
In simple words: Melatonin is a hormone made by your brain, especially when it's dark. It tells your body when to sleep and when to be awake, helping to keep your natural day and night cycle on track.

🎯 Exam Tip: Melatonin is always linked to the pineal gland and the regulation of circadian rhythms (sleep-wake cycles).

 

Question 10. Prabhu is working in a MNC Company. He has to do night shift once in every fifteen days. Aftern a few years he is suffering from sleeplessness (in somnia) What may be the cause of his problem.
(a) It may be becauses of his nature of work
(b) More work pressure
(c) The sleepwake cycle is disturbed due to the irregular synthesis of melotonin hormone
(d) Due to the metabolic disturbances
Answer: (c) The sleepwake cycle is disturbed due to the irregular synthesis of melotonin hormone
In simple words: Prabhu's night shifts mix up his body's natural clock. This stops his brain from making melatonin properly, which usually helps him sleep at night, leading to sleeplessness.

🎯 Exam Tip: Connect irregular work schedules directly to disruptions in melatonin production and the sleep-wake cycle for such case study questions.

 

Question 11. Name the structure that connects the lobes of thyroid gland?
(a) Acinus
(b) Ischium
(c) Isthmus
(d) bridge tissue
Answer: (c) Isthmus
In simple words: The thyroid gland has two main parts, called lobes. A small band of tissue, like a bridge, connects these two lobes. This connecting part is known as the isthmus.

🎯 Exam Tip: Knowing the anatomical terms for gland structures, like the isthmus of the thyroid, is crucial for biology exams.

 

Question 12. Name the element helps in the synthesis of thyroxine.
(a) Iron
(b) Calcium
(c) Iodine
(d) Sodium
Answer: (c) Iodine
In simple words: Your body needs a special element called iodine to make thyroxine. Without enough iodine, your thyroid gland cannot produce this important hormone correctly.

🎯 Exam Tip: Always remember that iodine is a primary requirement for the production of thyroid hormones like thyroxine.

 

Question 13. Assertion: The Oxyphil cells of parathyroid secrete parathormone Reason: The chief cells of parathyroid regulates the synthesis of parathormone
(a) Assertion and Reason are correct
(b) Assertion incorrect and reason is wrong
(c) The assertion is true. The reason is false
(d) Both the assertion and reason are false.
Answer: (d) Both the assertion and reason are false.
In simple words: Both parts of the statement are incorrect. It's the chief cells, not oxyphil cells, that make parathormone in the parathyroid gland. Also, the chief cells regulate its production, not the oxyphil cells.

🎯 Exam Tip: For assertion-reason questions, carefully evaluate both statements for their individual truth and then check if the reason correctly explains the assertion.

 

Question 14. Which of the functional features of hormone is not correctly matched with its description?
(a) Thyroid gland hormones often called the major metabolic hormones.
(b) Thyro calcitonin increases the blood calcium level
(c) The adrenalin is the emergency hormone.
(d) The functions of oxyphil cells are not known.
Answer: (b) Thyro calcitonin increases the blood calcium level
In simple words: The hormone thyrocalcitonin actually works to lower the calcium level in the blood. Therefore, the statement that it increases blood calcium is incorrect.

🎯 Exam Tip: Pay close attention to keywords like "increases" or "decreases" when dealing with hormone functions, as they often determine the correctness of a statement.

 

Question 15. Which of the following option shows the with its action matched hormones (given in column I) (given in column II)

(a) A – ii; B – iv; C – i; D – iii
(b) A – iv ; B – iii; C – ii; D – i
(c) A – iii; В – ii; C – iv; D – i
(d) A – iv; B – i; C – iii; D – ii
Answer: (b) A – iv ; B – iii; C – ii; D – i
In simple words: The correct match is: Pituitary gland (A) originates from Rathke's pouch (iv). Thyroid gland (B) makes thyroxine which controls metabolism (iii). Ovary (C) secretes oestrogen (ii). Thymus (D) is a partial endocrine gland involved in immunity (i).

🎯 Exam Tip: For matching questions, systematically go through each item in Column I and find its correct match in Column II to avoid errors.

 

Question 16. These are known as supra-renal glands.
(a) Thymus gland
(b) Pancreas
(c) Adrenal gland
(d) Ovary
Answer: (c) Adrenal gland
In simple words: Adrenal glands sit on top of the kidneys, which is why they are also called "supra-renal" glands. "Supra" means above, and "renal" refers to the kidneys.

🎯 Exam Tip: Understand the origin of scientific names; "supra-renal" directly tells you the location of the adrenal glands.

 

Question 17. Find out the hormone which are catecholamines.
(a) Thyroxine
(b) Insulin
(c) Adrenalin
(d) Glucagon
Answer: (c) Adrenalin
In simple words: Adrenalin, also called epinephrine, belongs to a group of hormones known as catecholamines. These hormones are important for the body's 'fight or flight' response.

🎯 Exam Tip: Remember adrenalin and nor-adrenalin as the primary catecholamines, known for their rapid stress response.

 

Question 18. Why there is an accumulation of ketone bodies in blood of diabetic melitus patients?
(a) due to the excessive consumption of liquids
(b) break down of fat in to glucose
(c) conversion of glucose from protein
(d) due to excessive in take of food
Answer: (b) break down of fat in to glucose
In simple words: In diabetic patients, the body cannot use glucose for energy properly. So, it starts breaking down fats instead. This breakdown creates ketone bodies, which then build up in the blood.

🎯 Exam Tip: Ketone body accumulation (ketosis) in diabetes is a key sign of the body relying on fat for energy due to impaired glucose metabolism.

 

Question 19. This hormone promotes the activation of Vitamin D thus by absorbing calcium?
(a) Calcitonin
(b) Thymosin
(c) Parathormone
(d) Thyroxine
Answer: (c) Parathormone
In simple words: Parathormone helps your body use vitamin D to take in more calcium from your food. This hormone is crucial for keeping calcium levels high enough in your blood and for healthy bones.

🎯 Exam Tip: Link parathormone directly to raising blood calcium levels, which involves both bone release and vitamin D activation for intestinal absorption.

 

Question 20. Which part of pancreas is act as a exocrine gland?
(a) Globules
(b) islets of Langerhans
(c) Acinus
(d) Globlets
Answer: (c) Acinus
In simple words: The pancreas has small structures called acini, which act as an exocrine gland. These acini produce and release digestive enzymes into the digestive system.

🎯 Exam Tip: Differentiate between the exocrine (acini, producing digestive enzymes) and endocrine (islets of Langerhans, producing hormones) functions of the pancreas.

 

Question 21. Name the cells that secrete somatostatin
(a) a cells
(b) b cells
(c) Lampda cells
(d) delta cells
Answer: (d) delta cells
In simple words: In the pancreas, special cells known as delta cells are responsible for making and releasing somatostatin. This hormone helps control the activity of other cells in the pancreas.

🎯 Exam Tip: For pancreatic cells, remember alpha cells secrete glucagon, beta cells secrete insulin, and delta cells secrete somatostatin.

 

Question 22. Why is insulin tablet not advisable for chronic diabetic mellitus patients?
(a) It takes more time to act
(b) The insulin find it difficult to reach the substrate
(c) Insulin is easily digested by the digestive enzymes
(d) The insulin is not a effective one.
Answer: (c) Insulin is easily digested by the digestive enzymes
In simple words: If insulin were taken as a tablet, the digestive juices in your stomach and intestines would break it down. This means it wouldn't reach the bloodstream whole and wouldn't be able to do its job of controlling blood sugar.

🎯 Exam Tip: Explain that insulin, being a protein hormone, is susceptible to breakdown by proteases in the digestive system, necessitating injection.

 

Question 23. This hormone is involved in the cyclic changes of menstruation.
(a) Testosterone
(b) Pitocin
(c) Oestrogen
(d) Progesterone
Answer: (c) Oestrogen
In simple words: Oestrogen is a key hormone that helps regulate a woman's menstrual cycle. It controls many changes in the body that happen each month, including preparing the uterus.

🎯 Exam Tip: Oestrogen and progesterone are the two main hormones regulating the menstrual cycle; clearly state their roles.

 

Question 24. Contraction of uterus leads to miscarriages in a pregnant womens. What would be administered to evacuate the embryo?
(a) ADH
(b) Vasopressin
(c) Androgen
(d) Oxytocin
Answer: (d) Oxytocin
In simple words: Oxytocin is a hormone that makes the uterus contract strongly. In cases of miscarriage, it can be given to help the uterus push out the embryo.

🎯 Exam Tip: Emphasize oxytocin's role in uterine contractions, not only during childbirth but also in medical procedures for embryo evacuation.

 

Question 25. In the case of thyrotecdomic patients what is advisable to given along with the thyroxine?
(a) Insulin
(b) Thyroglobulin
(c) Parathormone
(d) Adrenalin
Answer: (c) Parathormone
In simple words: Thyrotoxic patients usually have their thyroid gland removed or damaged. Since the parathyroid glands are very close to the thyroid, they might also be affected. Therefore, parathormone may be needed to keep calcium levels normal.

🎯 Exam Tip: Note the close anatomical relationship between the thyroid and parathyroid glands, which often leads to co-morbidities or iatrogenic damage during thyroid surgery.

 

Question 26. If a doctor finds a high level of atrial natriuretic factor in the blood of a patient what he will suspect?
(a) A patient is suffering from in sufficient oxygen supply
(b) A patient will have a heart attack due to high blood pressure
(c) Suspecting depression problem
(d) Many develop thrombosis
Answer: (b) A patient will have a heart attack due to high blood pressure
In simple words: A high level of atrial natriuretic factor (ANF) means the heart is under stress from high blood pressure. ANF tries to lower blood pressure, so if it's high, it suggests the body is fighting off high blood pressure, which can lead to heart problems.

🎯 Exam Tip: Remember ANF's role in blood pressure regulation; a high ANF level indicates the body's attempt to counteract elevated blood pressure.

 

Question 27. Name the hormone that stimulates the synthesis of HCl.
(a) Enterokinase
(b) Pepsinogen
(c) Gastrin
(d) Secretin
Answer: (c) Gastrin
In simple words: Gastrin is a hormone that tells the stomach to make more hydrochloric acid (HCl). This acid is important for digesting food.

🎯 Exam Tip: Associate gastrin with gastric acid (HCl) secretion, which is a fundamental concept in digestive physiology.

 

Question 28. What is the other name for type I diabetes?
(a) Insulin dependent diabetes
(b) Non-insulin dependent diabetes
(c) Sensitive diabetes
(d) Dependent types
Answer: (a) Insulin dependent diabetes
In simple words: Type I diabetes is also called insulin-dependent diabetes because people with this condition must take insulin injections every day. Their body cannot produce enough insulin on its own.

🎯 Exam Tip: Clearly distinguish Type I (insulin-dependent, autoimmune, juvenile onset) from Type II (non-insulin dependent, insulin resistance, adult onset) diabetes.

 

Question 29. Which is called as second messenger.
(a) Receptor cells
(b) CAMP
(c) Adenylate
(d) Substrate
Answer: (b) CAMP
In simple words: Cyclic AMP (cAMP) is known as a second messenger in cell signaling. It helps carry messages from hormones outside the cell to cause changes inside the cell.

🎯 Exam Tip: Understand the concept of first (hormone) and second (cAMP) messengers in cell signaling pathways.

 

Question 30. In the following diagram what are the parts A, B, C and D representing?
Answer: III) A) Infundibuim B) Posterior C) Hypophyseal vein D) Endocrine cells
In simple words: In the diagram showing the pituitary gland and hypothalamus, A points to the infundibulum (the stalk), B to the posterior lobe of the pituitary, C to the hypophyseal vein, and D to the endocrine cells. These parts work together to control many body functions.

🎯 Exam Tip: When presented with diagrams, clearly identify each labeled part and understand its function and connection to other parts.

 

Question 31. Find out the true and false statements from the following and on that basis find the correct answer.
(i) ADH causes blood vessels to dialate
(ii) The 'c' cells of thyroid gland secretes calcitonin
(iii) Zona fasciculate secretes cortisol
(iv) Minerals corticoids regulate water balance
(a) i) a) True b) False c) True
(b) ii) a) False b) True c) False
(c) iii) a) False b) True c) False
(d) iv) a) False b) False c) True
Answer: (d) iv) a) False b) False c) True
In simple words: Based on the information, the option (d) is the correct choice provided in the source. This indicates a complex evaluation where the truthfulness of specific statements within option (d) is considered the correct response.

🎯 Exam Tip: Carefully dissect complex multiple-choice questions with nested statements. Sometimes, the question asks you to identify the correct *option* based on an assessment of truthfulness, rather than simply identifying True/False values for each initial statement.

 

Question 32. Which part interlinks both the nervous system and endocrine system?
(a) Receptor molecules
(b) Target tissue
(c) Hypothalamus
(d) Infundibulum
Answer: (c) Hypothalamus
In simple words: The hypothalamus is a small but very important part of the brain that connects the nervous system with the endocrine system. It does this by making and sending out hormones that control the pituitary gland, which then controls other glands.

🎯 Exam Tip: The hypothalamus is the key bridge between the nervous and endocrine systems, often referred to as the "neuroendocrine control center."

 

Question 33. Which of the following disease is not caused by iodine or thyroxine deficiency?
(a) Sporodic goitre
(b) Exophthalmic goitre
(c) Simple goitre
(d) Myxodema
Answer: (a) Sporodic goitre
In simple words: Sporadic goiter is a type of goiter that is not caused by a lack of iodine or thyroxine. It happens for other reasons, unlike simple goiter which is directly linked to iodine deficiency.

🎯 Exam Tip: Differentiate between different types of goiter and their causes; simple goiter is iodine-deficient, while exophthalmic goiter is hyperthyroid (Grave's disease).

 

Question 34. Which is the correct location of the receptors of the hormones?
(a) Extracellular matrix
(b) Blood
(c) Plasma membrane
(d) Nucleus
Answer: (c) Plasma membrane
In simple words: Hormones, especially protein hormones, cannot easily enter cells. So, their special receptors are found on the outside surface of the cell, on the plasma membrane. For steroid hormones, receptors are inside the cell.

🎯 Exam Tip: Distinguish between cell surface receptors (for peptide hormones) and intracellular receptors (for steroid and thyroid hormones) based on hormone solubility.

 

Question 35. The primary target of the hormones of hypothalamus is
(a) pineal gland
(b) thymus
(c) testis
(d) pituitary
Answer: (d) pituitary
In simple words: The hormones made by the hypothalamus primarily travel to and act on the pituitary gland. The pituitary then releases its own hormones, which affect many other glands in the body.

🎯 Exam Tip: Remember the "hypothalamic-pituitary axis" as the central control system, where the hypothalamus regulates the pituitary.

 

Question 36. Functionally the adenohypophysis of pituitary gland includes
(a) anterior lobe
(b) Posterior lobe
(c) intermediate lobe
(d) both (a) and (c)
Answer: (d) both (a) and (c)
In simple words: The adenohypophysis is the front part of the pituitary gland. It includes both the anterior lobe and the intermediate lobe. These two parts work together to release many important hormones.

🎯 Exam Tip: Know that the pituitary gland is divided into anterior (adenohypophysis) and posterior (neurohypophysis) parts, each with distinct origins and functions. The adenohypophysis further includes the anterior and intermediate lobes.

 

Question 37. An outgrowth of hypothalamus from the base of the brain develops into
(a) pars nervosa
(b) pars intermedia
(c) pars distalis
(d) pars intermedia
Answer: (a) pars nervosa
In simple words: The pars nervosa, also known as the posterior pituitary, develops directly from an extension of the hypothalamus in the brain. It's a key part of how the brain controls hormone release.

🎯 Exam Tip: Differentiate the embryological origin: anterior pituitary (adenohypophysis) from Rathke's pouch (oral ectoderm), and posterior pituitary (neurohypophysis/pars nervosa) from a hypothalamic outgrowth (neuroectoderm).

 

Question 38. The hormone secreted by neurohypophysis is
(a) ACTH
(b) ADH
(c) GH
(d) TSH
Answer: (b) ADH
In simple words: The neurohypophysis, which is the posterior part of the pituitary gland, releases ADH (Antidiuretic Hormone). ADH helps your body control how much water it keeps.

🎯 Exam Tip: Note that neurohypophysis *releases* hormones (ADH and oxytocin) that are *produced* by the hypothalamus. It does not produce them itself.

 

Question 39. Among the following hormones which is the peptide hormone.
(a) GH
(b) TSH
(c) FSH
(d) LH
Answer: (a) GH
In simple words: GH, or Growth Hormone, is a type of hormone made of amino acid chains, which makes it a peptide hormone. Other options like TSH, FSH, and LH are glycoprotein hormones.

🎯 Exam Tip: Classify hormones by their chemical nature (peptide, steroid, amino acid derivative) as it relates to their synthesis, transport, and mechanism of action.

 

Question 40. Among the following which is not a glycoprotein hormone.
(a) TSH
(b) LTH
(c) LH
(d) FSH
Answer: (b) LTH
In simple words: LTH, also known as Prolactin, is a protein hormone, not a glycoprotein hormone. Glycoprotein hormones like TSH, LH, and FSH are made of protein parts linked to sugar chains.

🎯 Exam Tip: Memorize the key glycoprotein hormones (TSH, FSH, LH, HCG) and distinguish them from other hormone types like peptide/protein hormones (GH, Prolactin).

 

Question 41. Find out the protein hormone from the following.
(a) LTH
(b) FSH
(c) TSH
(d) ACTH
Answer: (a) LTH
In simple words: LTH, or Luteotropic hormone (Prolactin), is a protein hormone, meaning it's made up of amino acids. FSH and TSH are glycoprotein hormones, while ACTH is a peptide hormone.

🎯 Exam Tip: Review the major classifications of hormones based on their chemical structure (peptides, proteins, steroids, amino acid derivatives, glycoproteins) as this frequently appears in exams.

 

Question 42. Which is the pituitary hormone that is present in other vertebrates?
(a) MSH
(b) ACTH
(c) TSH
(d) GH
Answer: (a) MSH
In simple words: MSH, or Melanocyte-Stimulating Hormone, is a pituitary hormone found not only in humans but also in many other vertebrates. It plays a role in controlling skin color in some animals.

🎯 Exam Tip: Understand that MSH is produced by the intermediate lobe of the pituitary gland, which is more prominent in other vertebrates than in adult humans.

 

Question 43. Find out the wrong statement about vasopressin or ADH
(a) It promotes re-absorption of water and electrolytes by distal tubules of nephron.
(b) Causes constriction of blood vessels
(c) It stimulates vigorous contraction of smooth muscles of uterus during child birth
(d) It is a peptide hormone
Answer: (c) It stimulates vigorous contraction of smooth muscles of uterus during child birth
In simple words: Vasopressin (ADH) helps your body keep water and can narrow blood vessels. It is a peptide hormone. However, stimulating strong contractions of the uterus during childbirth is actually the job of oxytocin, not vasopressin.

🎯 Exam Tip: Differentiate clearly between the functions of ADH (water reabsorption, vasoconstriction) and oxytocin (uterine contractions, milk ejection).

 

Question 45. Posterior pituitary secretion is controlled by
(a) hypothalamic hypophyseal portal blood vessel
(b) neuro endocrine gland
(c) hypophysis
(d) hypothalamic hypophyseal axis
Answer: (d) hypothalamic hypophyseal axis
In simple words: The posterior pituitary gland, which is part of the endocrine system, receives commands from the hypothalamus through a special nerve connection called the hypothalamic hypophyseal axis. This connection helps control what hormones the posterior pituitary releases.

🎯 Exam Tip: Remember that the anterior pituitary is controlled by a portal system, while the posterior pituitary is controlled by nerve signals from the hypothalamus.

 

Question 46. Assertion: Adrenalin nor-adrenalin, melatonin and thyroid hormones are proteins
Reason: Derived from cholesterol mostly water soluble
(a) If both Assertion and Reason are correct
(b) If both Assertion and Reason and true but Reason is not the correct explanation of Assertion.
(c) If assertion is true but reason is false
(d) Both the assertion and reason are false.
Answer: (d) Both the assertion and reason are false.
In simple words: Adrenalin, nor-adrenalin, melatonin, and thyroid hormones are not all proteins. Also, hormones derived from cholesterol are lipid-soluble, not water-soluble.

🎯 Exam Tip: Categorize hormones based on their chemical nature (e.g., protein, steroid, amino acid derivative) to understand their properties and mechanisms of action.

 

Question 47. Assertion: Growth hormone stimulates chondrogenesis and osteogenesis
Reason: Growth hormones promote growth of all tissues and metabolic process of the body.
(a) If both Assertion and reason are true and reason is the correct explanation of assertion
(b) If both Assertion and reason and true but reason is not the correct explanation of Assertion.
(c) If assertion is true but reason is false
(d) If both Assertion and reason are false
Answer: (a) If both Assertion and reason are true and reason is the correct explanation of assertion
In simple words: Growth hormone helps in the formation of cartilage and bone, and it also boosts the growth and metabolic activities of all body tissues. This shows that promoting overall body growth is why it stimulates cartilage and bone growth.

🎯 Exam Tip: When evaluating assertion-reason questions, first check if both statements are individually true, then determine if the reason directly explains the assertion.

 

Question 48. Assertion: Adrenal medulla hormones are referred as 3F hormones fight, flight and hormones.
Reason: During emergency it increases heart beat rate and blood pressure
(a) If both Assertion and reason are true and reason is the correct explanation of assertion
(b) If both Assertion and reason and true but reason is not the correct explanation of Assertion.
(c) If assertion is true but reason is false
(d) If both Assertion and reason are false
Answer: (a) If both Assertion and reason are true and reason is the correct explanation of assertion
In simple words: The hormones from the adrenal medulla are called "3F hormones" (fight, flight, fright) because they prepare the body for stress. This happens because they increase heart rate and blood pressure during emergencies, which is a direct effect of these hormones.

🎯 Exam Tip: The "fight or flight" response is a classic example of endocrine system regulation in stress; linking specific hormones (like adrenaline) to their immediate physiological effects is key.

 

Question 49. Assertion: The effects of aldosterone, oestrogen FSH are long lived as they alter the amount of m- RNA and protein in a cell
Reason: The action of cAMP are terminated by phosphodiesterases
(a) If both Assertion and reason are true and reason is the correct explanation of assertion
(b) If both Assertion and reason and true but reason is not the correct explanation of Assertion.
(c) If assertion is true but reason is false
(d) If both Assertion and reason are false
Answer: (b) If both Assertion and reason and true but reason is not the correct explanation of Assertion.
In simple words: Aldosterone, oestrogen, and FSH do have long-lasting effects because they change the amount of mRNA and proteins in cells. The action of cAMP is indeed stopped by phosphodiesterases. Both statements are true, but the reason does not explain why the effects of these hormones are long-lived.

🎯 Exam Tip: Understand the difference between hormone classes: steroid hormones (like aldosterone and oestrogen) often act by influencing gene expression, leading to longer-term effects, while protein hormones (like FSH) often use second messengers like cAMP.

 

Question 50. Assertion: The immunity of old age people, becomes week and causes sickness.
Reason: Due to degeneration of pineal gland thymosin level decreases
(a) If both Assertion and reason are true and reason is the correct explanation of assertion
(b) If both Assertion and reason and true but reason is not the correct explanation of Assertion.
(c) If assertion is true but reason is false
(d) If both Assertion and reason are false
Answer: (c) If assertion is true but reason is false
In simple words: Older people often have weaker immune systems and get sick more easily. However, this is mainly because the thymus gland degenerates, causing a decrease in thymosin, not the pineal gland. The pineal gland makes melatonin, which is related to sleep.

🎯 Exam Tip: Connect glands to their specific hormones and primary functions; the thymus is crucial for immune function, particularly T-lymphocyte maturation.

 

Question 51. Assertion: JGA cells of the kidney stimulates erythropoiesis or formation of RBC
Reason: JGA cells also secrete Erythropoietin
(a) If both Assertion and reason are true and reason is the correct explanation of assertion
(b) If both Assertion and reason and true but reason is not the correct explanation of Assertion.
(c) If assertion is true but reason is false
(d) If both Assertion and reason are false
Answer: (a) If both Assertion and reason are true and reason is the correct explanation of assertion
In simple words: The JGA cells in the kidney do stimulate the making of red blood cells. This is because these cells produce erythropoietin, which is a hormone that specifically tells the bone marrow to create more red blood cells.

🎯 Exam Tip: Remember the critical role of the kidneys in hormone production, especially erythropoietin, which links directly to red blood cell formation.

 

Question 52. Assertion: Diabetes inspidus is marked by production of large amount of urine.
Reason: Hypo secretion of ADH leads to a condition of reduced water absorption. Thus the urine becomes diluted without sugar or glucose
(a) If both Assertion and reason are true and reason is the correct explanation of assertion
(b) If both Assertion and reason and true but reason is not the correct explanation of Assertion.
(c) If assertion is true but reason is false
(d) If both Assertion and reason are false
Answer: (a) If both Assertion and reason are true and reason is the correct explanation of assertion
In simple words: Diabetes insipidus causes a person to produce a lot of urine. This happens because the body doesn't make enough ADH hormone, which normally helps the kidneys reabsorb water, so less water is absorbed, and the urine becomes watery without sugar.

🎯 Exam Tip: Differentiate between Diabetes Mellitus (sugar-related) and Diabetes Insipidus (water balance-related), focusing on the hormones and symptoms involved.

 

Question 53. The Luteinizing hormone in males is
(a) Testosterone
(b) ICSH
(c) FSH
(d) LTH
Answer: (b) ICSH
In simple words: In males, Luteinizing Hormone (LH) is also known as Interstitial Cell Stimulating Hormone (ICSH). This hormone plays a key role in stimulating the Leydig cells in the testes to produce testosterone.

🎯 Exam Tip: Understand that LH has different names or specific roles depending on gender, like ICSH in males, which highlights its action on interstitial cells.

 

Question 54. The cells that secrete parathyroid hormone is knows as
(a) chief cells
(b) oxyphil cells
(c) goblet
(d) both b and c cells
Answer: (a) chief cells
In simple words: The parathyroid hormone, which helps control calcium levels in the body, is mainly produced by special cells in the parathyroid glands called chief cells. These cells are essential for maintaining proper calcium balance.

🎯 Exam Tip: Associate specific hormones with the cells or glands that produce them; chief cells are the primary producers of parathyroid hormone.

 

Question 55. Find out the correct statement about pineal gland.
(a) Stimulates the production and release of sperms.
(b) Increases blood pressure.
(c) It plays a central role and the regulation of circadian rhythm of our body and maintains the normal sleep wake cycle.
(d) It is about 1cm in diameter and 0.5gm.
Answer: (c) It plays a central role and the regulation of circadian rhythm of our body and maintains the normal sleep wake cycle.
In simple words: The pineal gland is very important because it helps control our body's natural 24-hour clock, called the circadian rhythm. This means it helps us stay on a normal sleep-wake schedule.

🎯 Exam Tip: The pineal gland's primary function is linked to melatonin secretion and the regulation of sleep patterns and circadian rhythms.

 

Question 56. The BMR is regulated by
(a) Parathormone
(b) Thyrocalcitonin
(c) Adrenalin
(d) Thyroxine
Answer: (d) Thyroxine
In simple words: Thyroxine, a hormone produced by the thyroid gland, is responsible for controlling our Basal Metabolic Rate (BMR). This hormone essentially sets the speed at which our body uses energy when at rest.

🎯 Exam Tip: The thyroid hormones, especially thyroxine, are the main regulators of metabolism and body temperature, a key concept for understanding metabolic disorders.

 

Question 57. The primary function of thymus gland is
(a) regulation of body temperature
(b) regulation of body growth
(c) immunological functions
(d) Secretion of thyrotropin
Answer: (c) immunological functions
In simple words: The main job of the thymus gland is to help our body's immune system. It specifically helps special immune cells, called T-lymphocytes, mature so they can fight off infections.

🎯 Exam Tip: Focus on the thymus gland's specific role in immunity, particularly its involvement in T-cell maturation and adaptive immune responses.

 

Question 58. A hormone secreted by adrenal gland and called life-saving hormone is
(a) adrenaline
(b) cortisone
(c) aldosterone
(d) Cortisol
Answer: (d) Cortisol
In simple words: Cortisol, a hormone made by the adrenal glands, is often called a "life-saving hormone." It plays many important roles, especially in how the body responds to stress and maintains blood sugar levels.

🎯 Exam Tip: Cortisol is a glucocorticoid crucial for stress response, inflammation control, and blood glucose regulation; it's often essential for survival in extreme stress.

 

Question 59. Which of the following condition is not linked to a deficiency of thyroid hormone?
(a) cretinism
(b) goitre
(c) Myxoedema
(d) Exophthalmia
Answer: (d) Exophthalmia
In simple words: Cretinism, goitre, and myxoedema are all conditions caused by not having enough thyroid hormone. However, exophthalmia, which involves bulging eyes, is usually a symptom of having too much thyroid hormone, not too little.

🎯 Exam Tip: Clearly distinguish between hyperthyroidism (excessive thyroid hormone) and hypothyroidism (deficient thyroid hormone) symptoms to avoid confusion.

 

Question 60. Androgens are sex corticoids secreted from
(a) Zona reticulate
(b) Adrenal medulla
(c) Zona glomerulosa
(d) Acini
Answer: (a) Zona reticulate
In simple words: Androgens, which are a type of sex hormone, are produced in the adrenal cortex. Specifically, they come from the innermost layer of the adrenal cortex called the zona reticularis.

🎯 Exam Tip: Recall the three layers of the adrenal cortex (glomerulosa, fasciculata, reticularis) and the main hormones each layer produces.

 

Question 61. A gland which is well developed in newborn child and produce lymphocytes
(a) Thyroid gland
(b) Thymus
(c) Parathyroid gland
(d) Pineal gland
Answer: (b) Thymus
In simple words: The thymus gland is quite large and active in babies and young children. Its main job is to make and mature special white blood cells called lymphocytes, which are crucial for the body's immune system.

🎯 Exam Tip: The thymus is unique because it's largest in childhood and then shrinks, reflecting its crucial role in early immune system development.

 

Question 62. Which one reduces the blood calcium level and shows an opposite effect to parathormone?
(a) ADH
(b) Insulin
(c) Thyrocalcitonin
(d) Thyroxine
Answer: (c) Thyrocalcitonin
In simple words: Thyrocalcitonin, a hormone from the thyroid gland, helps lower calcium levels in the blood. It works against parathormone, which does the opposite job of raising blood calcium. Together, they keep calcium balanced.

🎯 Exam Tip: Understand the antagonistic relationship between calcitonin (from thyroid) and parathyroid hormone in regulating blood calcium levels.

 

Question 63. Secretion of HCI and pepsinogen is controlled by
(a) Cholecystokinin
(b) Gastrin
(c) Calcitriol
(d) Renin
Answer: (b) Gastrin
In simple words: The stomach's ability to produce hydrochloric acid (HCl) and pepsinogen, which are important for digestion, is controlled by a hormone called gastrin. Gastrin tells the stomach to get ready for food by releasing these substances.

🎯 Exam Tip: Gastrin is a key hormone in the digestive system that stimulates gastric acid secretion, important for protein digestion.

 

Question 64. A man has an IQ equivalent to that of a boy 5 years old this is due to the deficiency of which hormone?
(a) Thyroxine
(b) Adrenaline
(c) Aldosterone
(d) Somatotropin
Answer: (a) Thyroxine
In simple words: If a person's mental development is severely delayed, like that of a young child, it can be caused by a lack of thyroxine hormone. Thyroxine is crucial for normal brain development, especially during childhood.

🎯 Exam Tip: Emphasize the vital role of thyroid hormones in neurological development and cognitive function, especially in early life.

 

Question 65. Which of the following option shows the correct matching of disorder's and causes.
A) Addison's disease -(i) Hypo secretion of thyroid
B) Cushing's syndrome – (ii) Hyper secretion of parathyroid hormone
C) Softening of bone – (iii) Hypo secretion of gluco corticoids
D) Gull's disease (in adults) – (iv) Excess secretion of cortisol
Codes:
(a) A – (ii); B – (i); C – (iii); D – (iv)
(b) A – (iii); B – (iv); C – (ii); D – (i)
(c) A – (iii); B – (ii); C – (i); D – (iv)
(d) A – (iv); B – (iii); C – (iv); D – (ii)
Answer: (b) A – (iii); B – (iv); C – (ii); D – (i)
In simple words: Let's match the disorders with their correct causes. Addison's disease is caused by too little glucocorticoid hormone. Cushing's syndrome happens when there's too much cortisol. Softening of bones is linked to too much parathyroid hormone. Gull's disease, also known as myxoedema in adults, is caused by too little thyroid hormone.

🎯 Exam Tip: Create a mental map of endocrine disorders, linking each one to a specific gland, its hormone, and whether there's an excess (hyper) or deficiency (hypo).

 

Question 66. A person is having problems with calcium and phosphorous metabolism in his body.
Which one of the following glands may not be functioning
(a) Parathyroid
(b) Parotid
(c) Pancreas
(d) Thyroid
Answer: (a) Parathyroid
In simple words: If someone is having trouble with how their body handles calcium and phosphorus, it's very likely that their parathyroid gland is not working properly. This gland produces hormones that are key to keeping these mineral levels balanced.

🎯 Exam Tip: The parathyroid glands are the primary regulators of calcium and phosphate metabolism, so problems in these areas often point directly to parathyroid dysfunction.

 

Question 67. Presence of fat and acid in the diet induces the secretion of
(a) Gastrin
(b) Secretion
(c) Cholecystokinin
(d) Calcitrol
Answer: (c) Cholecystokinin
In simple words: When fatty and acidic foods enter the digestive system, a hormone called cholecystokinin (CCK) is released. This hormone helps with digestion by telling the gallbladder to release bile and stimulating the pancreas to release digestive enzymes.

🎯 Exam Tip: Cholecystokinin (CCK) is a crucial gastrointestinal hormone that coordinates gallbladder contraction and pancreatic enzyme secretion in response to food, particularly fats.

 

Question 68. Which is an amino acid derivative hormone?
(a) Epinephrine
(b) Oestrogen
(c) Progesterone
(d) Relaxin
Answer: (a) Epinephrine
In simple words: Epinephrine, also known as adrenaline, is a hormone that comes from amino acids. Hormones can be grouped into different types based on what they are made of.

🎯 Exam Tip: Review the different chemical classes of hormones (e.g., steroid, peptide, amino acid derivative) and be able to identify examples for each category.

 

Question 69. Which of the following is a mineralococticoid?
(a) Testosterone
(b) Cortisol
(c) Adrenalin
(d) Aldosterone
Answer: (d) Aldosterone
In simple words: Aldosterone is a hormone that helps control the balance of salt and water in the body, which is why it's called a mineralocorticoid. It's produced by the adrenal glands.

🎯 Exam Tip: Aldosterone is the primary mineralocorticoid, crucial for maintaining electrolyte balance and blood pressure by acting on the kidneys.

 

Question 70. Which hormone increases the rate of protein biosynthesis chondrogenesis and osteogenesis and helps in the retention of minerals?
(a) Prolactin
(b) Somatotrophic hormone
(c) Thyrotropin
(d) Glucagon
Answer: (b) Somatotrophic hormone
In simple words: Somatotrophic hormone, also known as growth hormone (GH), is responsible for increasing the creation of proteins, forming cartilage, and making bones stronger. It also helps the body keep important minerals. This hormone is vital for overall growth and development.

🎯 Exam Tip: Somatotrophic hormone (GH) is a multi-functional hormone, remember its broad effects on growth, metabolism, and mineral balance.

 

Question 71. The male sex hormones are secreted by
(a) Zona glomerulosa
(b) Fat cells
(c) Lay-dig cells
(d) Acini
Answer: (c) Lay-dig cells
In simple words: The main male sex hormones, like testosterone, are produced by special cells called Leydig cells. These cells are found in the testes and are important for male development and reproduction.

🎯 Exam Tip: Leydig cells are the primary site of androgen (male sex hormone) synthesis in the testes, stimulated by luteinizing hormone (LH).

 

Question 72. Which of the following pituitary hormone is secreted without the involvement of a releasing hormone?
(a) Thyrotropin
(b) Follicle stimulating hormone
(c) Oxytocin
(d) Prolactin
Answer: (c) Oxytocin
In simple words: Oxytocin is a special hormone released by the pituitary gland without needing a separate "releasing hormone" from the hypothalamus. Instead, nerve signals from the hypothalamus directly tell the pituitary to release oxytocin. This hormone is crucial for childbirth and milk ejection.

🎯 Exam Tip: Differentiate between anterior pituitary hormones (mostly regulated by hypothalamic releasing/inhibiting hormones) and posterior pituitary hormones (like oxytocin and ADH, which are neurohormones produced by the hypothalamus and released by the pituitary).

 

Question 73. Match the following columns.

Code:
(a) A - 4; B - 3; C - 2; D - 1
(b) A - 3; B - 1; C - 4; D - 2
(c) A - 2; B - 4; C - 3; D - 1
(d) A - 1; B - 2; C - 4; D - 3
Answer: (b) A - 3, B - 1, C - 4, D - 2
In simple words: Let's match each item. Melatonin controls our sleep-wake cycle. The Thymus gland is important for T-lymphocyte formation, which helps with immunity. Insulin is a hypoglycemic hormone, meaning it lowers blood sugar. Erythropoietin (which might be what "Trythropoietin" refers to) helps in the formation of red blood cells.

🎯 Exam Tip: For matching questions, eliminate obvious pairs first to narrow down options, and double-check each match to ensure accuracy.

 

Question 74. Which hormones can easily pass through the cell membrane and bind to their receptors and alter gene function?
(a) Peptide hormones
(b) Amino acid derived hormones
(c) Neuro hormones
(d) Steroid hormones
Answer: (d) Steroid hormones
In simple words: Steroid hormones are special because they are made of fat-like substances, which allows them to easily pass through the cell's outer membrane. Once inside, they attach to receptors and directly change how genes work, leading to longer-lasting effects.

🎯 Exam Tip: Remember that lipid-soluble hormones (like steroids) typically act intracellularly by affecting gene expression, while water-soluble hormones (like peptides) often act on surface receptors via second messengers.

 

Question 75. The hormone which helps to find out conception is
(a) FSH
(b) Oestrogen
(c) HCG
(d) LH
Answer: (c) HCG
In simple words: Human Chorionic Gonadotropin (HCG) is the hormone that indicates a woman is pregnant. It is produced after a fertilized egg implants in the uterus, and its presence is what pregnancy tests detect.

🎯 Exam Tip: HCG is the specific hormone used in pregnancy tests because it's produced by the developing embryo soon after conception.

 

Question 76. Gigantism and Acromegaly are due to
(a) Hypothyroidism
(b) Hyperthyroidism
(c) Hypopituitarism
(d) Hyper pitituitarism
Answer: (d) Hyper pitituitarism
In simple words: Gigantism, which causes excessive growth in children, and acromegaly, which causes enlarged features in adults, are both caused by too much activity of the pituitary gland. Specifically, they result from an overproduction of growth hormone.

🎯 Exam Tip: Differentiate gigantism (excess GH before puberty) from acromegaly (excess GH after puberty), both stemming from pituitary hypersecretion.

 

Question 77. After performing the functions in the target organs how hormones are inactivated and excreted?
(a) By intestine
(b) By lungs and skin
(c) By liver and Kidney
(d) Both a and b
Answer: (c) By liver and Kidney
In simple words: Once hormones have done their job in the body, they don't stay active forever. The liver breaks them down into inactive forms, and then the kidneys help to remove these inactive forms from the body, usually through urine.

🎯 Exam Tip: The liver and kidneys are crucial for hormone metabolism and excretion, ensuring that hormone levels are tightly regulated and excess hormones are removed from the body.

 

Question 78. The half life period of insulin is
(a) 6 minutes
(b) 8 minutes
(c) 15 minutes
(d) 7 minutes
Answer: (a) 6 minutes
In simple words: Insulin, a hormone that controls blood sugar, stays active in the body for only a short time. Its half-life, which is how long it takes for half of the hormone to be removed or broken down, is about 6 minutes. This short lifespan allows for quick and precise regulation of blood glucose.

🎯 Exam Tip: Knowing the half-life of hormones helps understand their speed and duration of action, which is particularly important for rapidly acting hormones like insulin.

 

Question 79. The time taken by insulin to be cleared from circulation is
(a) 10 -20 minutes
(b) 10-15 minutes
(c) 5 – 10 minutes
(d) 2-10 minutes
Answer: (b) 10-15 minutes
In simple words: Insulin does not stay in the bloodstream for a long time. It typically takes about 10 to 15 minutes for the insulin to be removed from the blood circulation after it has done its job of helping cells absorb sugar. This quick clearance allows for fine-tuning of blood sugar levels.

🎯 Exam Tip: The rapid clearance of insulin highlights the body's need for precise and quick control over blood glucose, preventing prolonged effects.

II. Very Short Answer

 

Question 1. What is the causes of bone cyst formation?
Answer: Bone cysts can form due to hyperparathyroidism, where too much parathyroid hormone is produced. This excessive hormone leads to the demineralization of bones, making them fragile and soft, and can cause cysts to develop within the bone structure.
In simple words: Bone cysts happen when the parathyroid gland makes too much hormone. This makes bones lose minerals and become soft, which can lead to cysts.

🎯 Exam Tip: Link bone demineralization and cyst formation directly to an imbalance of parathyroid hormone, emphasizing its role in calcium regulation.

 

Question 2. Why is the hypothalamus considered a neuroendocrine gland?
Answer: The hypothalamus is called a neuroendocrine gland because it performs both nervous system functions and endocrine system functions. It directly produces hormones while also being part of the brain, linking the nervous system to the endocrine system through the pituitary gland. It essentially acts as a bridge between nerve signals and hormone release.
In simple words: The hypothalamus is a neuroendocrine gland because it's part of the brain but also makes and releases hormones, connecting our nervous and endocrine systems.

🎯 Exam Tip: The hypothalamus is a crucial "control center," integrating neural input with hormonal output, demonstrating the interconnectedness of body systems.

 

Question 3. What is the meaning of the word hormone?
Answer: The word "hormone" comes from the Greek word "horman," which means "to excite" or "to set in motion." This perfectly describes how hormones work in the body, as they act as chemical messengers that stimulate or regulate various physiological processes. Hormones are crucial for maintaining balance and coordinating different body functions.
In simple words: "Hormone" means "to excite." Hormones are like chemical messengers that tell different parts of the body what to do, starting reactions and keeping things working smoothly.

🎯 Exam Tip: Understanding the etymology of scientific terms can often provide a deeper insight into their function and historical context.

 

Question 4. Write on the origin of the pituitary gland?
Answer: The pituitary gland has a dual origin. Its anterior lobe (adenohypophysis) develops from an embryonic outgrowth of the pharyngeal epithelium called Rathke's pouch. In contrast, the posterior lobe (neurohypophysis) originates as an outgrowth from the base of the brain, specifically the hypothalamus. This unique development explains the different functional connections of its two main parts to the brain.
In simple words: The pituitary gland comes from two different places when a baby is forming. The front part grows from the roof of the mouth (Rathke's pouch), and the back part grows out from the brain.

🎯 Exam Tip: Note the dual embryonic origin of the pituitary gland; this helps explain why its anterior and posterior lobes have different regulatory mechanisms.

 

Question 5. What is meant by Homeostasis?
Answer: Homeostasis refers to the body's ability to maintain a stable and constant internal environment despite changes in external conditions. This crucial process is achieved through the coordinated efforts of various systems, including the endocrine and nervous systems, which work together to regulate factors like temperature, pH, and blood sugar levels. Maintaining homeostasis is essential for the survival and proper functioning of an organism.
In simple words: Homeostasis is when your body keeps its inside conditions, like temperature or sugar levels, steady and balanced, even if outside changes. It's how the body stays healthy and works well.

🎯 Exam Tip: Homeostasis is a fundamental biological concept; understand it as dynamic equilibrium, not a static state, and be able to provide examples of regulatory mechanisms.

 

Question 6. What is Pars nervosa?
Answer: Pars nervosa is another name for the posterior lobe of the pituitary gland, also known as the neurohypophysis. This part of the pituitary gland is an extension of the hypothalamus and is primarily involved in storing and releasing hormones like oxytocin and antidiuretic hormone (ADH), which are actually produced by the hypothalamus. It acts as a storage and release site rather than producing its own hormones.
In simple words: Pars nervosa is just another name for the back part of the pituitary gland, also called the neurohypophysis. It stores and releases hormones that the brain makes.

🎯 Exam Tip: Recognize that the posterior pituitary (neurohypophysis/pars nervosa) is distinct from the anterior pituitary in that it releases hormones synthesized by the hypothalamus, rather than producing its own.

 

Question 7. Give example for partial endocrine glands.
Answer: Partial endocrine glands are organs that have other primary functions but also secrete hormones. Examples include the pancreas (which also has digestive functions), the gastrointestinal tract epithelium (involved in digestion), kidneys (excretion), heart (pumping blood), gonads (reproduction), and the placenta (supports pregnancy). These organs have specialized tissues that produce hormones alongside their main roles.
In simple words: Partial endocrine glands are organs that do more than just make hormones. Good examples are the pancreas, which helps digest food but also makes insulin, and the kidneys, which clean blood but also make hormones that help make red blood cells.

🎯 Exam Tip: Many organs have dual functions, acting as both exocrine/non-endocrine glands and endocrine glands; focus on the examples given and their hormonal contributions.

 

Question 8. Write a paragraph on the Growth Hormone?
Answer: Growth hormone (GH), also known as somatotropic hormone (STH) or somatotropin, is a peptide hormone vital for the body's growth and metabolic processes. It promotes the development of all tissues and directly influences the metabolism of carbohydrates, proteins, and lipids. GH also boosts protein production within cells and stimulates cartilage and bone formation. Additionally, it helps the body retain essential minerals like nitrogen, potassium, phosphorus, and sodium. A critical function is its role in conserving glucose for brain-dependent tissues by increasing fatty acid release from fat tissue and decreasing cellular glucose utilization for energy. This complex action ensures coordinated growth and energy management. In essence, GH orchestrates the body's growth and energy usage.
In simple words: Growth hormone, also called GH, helps your body grow taller and stronger. It makes sure your tissues and bones grow, helps your body use food for energy, and keeps important minerals inside you. It also saves sugar for your brain to use.

🎯 Exam Tip: When discussing growth hormone, highlight its broad impact on both skeletal/tissue growth and its significant role in regulating macronutrient metabolism.

 

Question 9. Name the hormone of peptide nature?
Answer: Hormones made of peptides include insulin, glucagon, and pituitary hormones. These hormones are water-soluble, meaning they can dissolve in water easily.
In simple words: Insulin, glucagon, and hormones from the pituitary gland are all made of peptides and dissolve in water.

🎯 Exam Tip: Remember that peptide hormones are water-soluble, which affects how they interact with cells, typically binding to surface receptors rather than entering the cell.

 

Question 10. What are steroid hormones?
Answer: Steroid hormones come from cholesterol and can dissolve in lipids (fats). Examples include cortisol, aldosterone, testosterone, oestrogen, and progesterone. These hormones play many important roles in the body, from stress response to reproduction.
In simple words: Steroid hormones are made from cholesterol and are fat-soluble. Examples are cortisol and testosterone.

🎯 Exam Tip: Steroid hormones are lipid-soluble, allowing them to pass through cell membranes and bind to receptors inside the cell.

 

Question 11. What is the role of Follicle stimulating hormone in man?
Answer: In men, Follicle-stimulating hormone (FSH) acts on the germinal epithelium in the seminiferous tubules. It helps to start and release sperm production. This process is essential for male fertility.
In simple words: In men, FSH helps the body make and release sperm from special tubes.

🎯 Exam Tip: When answering about hormones, always specify the target organ and the resulting physiological effect.

 

Question 12. What is the function of LH in female?
Answer: In females, Luteinizing Hormone (LH) causes ovulation, which is the release of an egg from the ovary. It also helps keep the corpus luteum working and promotes the creation and release of other ovarian hormones. This process is crucial for the menstrual cycle and potential pregnancy.
In simple words: In women, LH causes an egg to be released, helps a special structure in the ovary work, and makes other female hormones.

🎯 Exam Tip: Differentiate between the roles of FSH and LH in females, as both are crucial but have distinct functions in the ovarian cycle.

 

Question 13. Why there is a short life span for hormone-like insulin?
Answer: Hormones like insulin usually have a short lifespan because they work through a second messenger system, like cAMP. This system allows for rapid and temporary effects. Once its job is done, the hormone is quickly broken down to prevent overstimulation and maintain balance.
In simple words: Insulin works fast and quickly disappears because it uses a quick messenger system inside cells.

🎯 Exam Tip: Understanding the difference between hormones that use second messengers (like insulin) and those that bind to intracellular receptors (like steroids) is key to explaining their lifespan and action.

 

Question 14. Why the hormones steroid may be long-lived?
Answer: Steroid hormones tend to be long-lived because they change the amount of mRNA and protein in a cell. This means their effects last longer. For example, hormones like aldosterone, oestrogen, and FSH can have effects that persist for a significant duration.
In simple words: Steroid hormones last a long time because they change how cells make proteins, making their effects stay for longer.

🎯 Exam Tip: Remember that steroid hormones affect gene expression, leading to the synthesis of new proteins, which explains their prolonged effects compared to peptide hormones.

 

Question 15. How do the hormones reach and act on the specific target organs?
Answer: Hormones are released into the blood and travel throughout the body as chemical signals. They act only on specific target organs because these organs have special receptor molecules. These receptors can be either on the cell surface or inside the cell, and only cells with the right receptors will respond to a particular hormone. This ensures hormones act precisely where needed.
In simple words: Hormones travel in the blood and work only on certain organs. These organs have special spots (receptors) that fit the hormone, like a key in a lock.

🎯 Exam Tip: The "lock and key" model is a good analogy to explain hormone-receptor specificity, emphasizing why hormones only affect certain target cells.

 

Question 16. Name the three zones which are present in the Adrenal gland.
Answer: The adrenal cortex has three main layers, or zones. These are the zona glomerulosa, the zona fasciculata, and the zona reticularis. Each zone produces different types of hormones that help the body manage stress, fluid balance, and other vital functions.
In simple words: The three layers of the adrenal gland are zona glomerulosa, zona fasciculata, and zona reticularis.

🎯 Exam Tip: It is important to know the names of these three zones and the main hormones each produces for detailed answers.

 

Question 17. Differentiate amines and steroid hormones
Answer:

In simple words: Amine hormones dissolve in water and come from amino acids, like adrenaline. Steroid hormones dissolve in fat and come from cholesterol, like cortisol.

🎯 Exam Tip: Focus on solubility (water vs. lipid) and origin (amino acid derivatives vs. cholesterol derivatives) as key differentiating factors.

 

Question 18. Differentiate exocrine glands from endocrine glands.
Answer:

In simple words: Exocrine glands use tubes (ducts) to send their products, like sweat or saliva, to surfaces. Endocrine glands release hormones directly into the blood without ducts, like the thyroid gland.

🎯 Exam Tip: The presence or absence of ducts is the most crucial distinction. Exocrine glands have ducts; endocrine glands are ductless.

 

Question 19. How endocrine glands be classified based on their secretary function?
Answer: Endocrine glands can be classified into three types based on how they secrete hormones:

• Exclusive endocrine glands: These glands only produce hormones. Examples include the pituitary, thyroid, parathyroid, pineal, and adrenal glands. They are dedicated solely to hormone production.
• Neuro endocrine gland: The hypothalamus is an example. It connects the nervous system with the endocrine system, releasing hormones that control other glands.
• Partial endocrine glands: These organs have other main functions but also contain endocrine tissues that produce hormones. Examples include the pancreas, gastrointestinal tract epithelium, kidneys, heart, gonads, and placenta.

In simple words: Endocrine glands are grouped by how they work: some only make hormones (like the thyroid), some link nerves and hormones (like the hypothalamus), and some have other jobs but also make hormones (like the pancreas or heart).

🎯 Exam Tip: When classifying, always provide examples for each category to illustrate your understanding clearly.

 

Question 20. Pituitary gland is known as master endocrine glands. Justify the statement.
Answer: The pituitary gland is often called the "master endocrine gland" because it controls the activity of many other endocrine glands. However, this statement isn't completely accurate. The pituitary gland itself is controlled by the hypothalamus, which contains special neurosecretory cells. These cells produce neurotransmitters that either release or stop the pituitary's secretions. So, while the pituitary controls many glands, the hypothalamus is its ultimate controller.
In simple words: The pituitary gland is called the "master gland" because it controls other glands. But actually, another part of the brain called the hypothalamus controls the pituitary gland.

🎯 Exam Tip: While "master gland" is a common term, remember to explain the hypothalamus's role in controlling the pituitary to give a complete and accurate answer.

 

Question 21. Write about the location and dimension of pituitary gland.
Answer: The pituitary gland is located in a bony hollow called the sella turcica, which is at the base of the brain in the sphenoid bone. This means it is also close to the hypothalamus. The gland is quite small, measuring about one centimeter in diameter and weighing approximately 0.5 grams. Its small size belies its extensive functions in the body.
In simple words: The pituitary gland sits in a small bone hollow at the base of the brain. It is about 1 cm wide and weighs around 0.5 grams.

🎯 Exam Tip: When describing location, mention specific anatomical landmarks like the sella turcica and sphenoid bone for precision.

 

Question 22. What is infundibulum?
Answer: The infundibulum is a stalk-like structure that connects the pituitary gland to the hypothalamus in the brain. It serves as a vital link, allowing for direct communication and transport of hormones between these two important endocrine centers. This connection is essential for regulating many bodily functions.
In simple words: The infundibulum is a stalk that connects the pituitary gland to the hypothalamus in the brain.

🎯 Exam Tip: The infundibulum's primary function is to provide a physical and functional link, enabling neural and hormonal communication.

 

Question 23. What is Rathke's pouch?
Answer: Rathke's pouch is an embryonic structure that forms as an upward growth from the roof of the mouth, specifically from the pharyngeal epithelium. This pouch later develops into the anterior lobe of the pituitary gland. This developmental origin explains the distinct tissues found in the anterior pituitary compared to the posterior pituitary.
In simple words: Rathke's pouch is a part in an embryo that grows from the mouth and later becomes the front part of the pituitary gland.

🎯 Exam Tip: Understanding embryonic origins like Rathke's pouch helps clarify the distinct developmental pathways of different parts of the pituitary gland.

 

Question 24. Comment on MSH or Melanocyte stimulating hormone.
Answer: Melanocyte Stimulating Hormone (MSH) plays a role in influencing skin pigmentation. In mammals, the pars intermedia (the part of the pituitary that secretes MSH) is not very important. However, in other vertebrates, the pars intermedia produces MSH, which then leads to changes in skin color. So, MSH primarily works to cause pigmentation in the skin.
In simple words: MSH is a hormone that makes skin darker. It is not very important in mammals but affects skin color in other animals.

🎯 Exam Tip: Remember that MSH's role in pigmentation is more pronounced in lower vertebrates than in most mammals.

 

Question 25. What are the functions of pineal gland?
Answer: The pineal gland, also known as the epiphysis cerebri or conarium, is located behind the brain's third ventricle. It is made of parenchymal and interstitial cells. This gland secretes melatonin, a hormone vital for regulating our body's daily sleep-wake cycle (circadian rhythm). Melatonin also helps control the timing of sexual maturity, affects metabolism, pigmentation, the menstrual cycle, and the body's defense mechanisms. It is a very versatile gland.
In simple words: The pineal gland makes melatonin, which controls our sleep and wake cycle. It also helps with sexual development, metabolism, skin color, and our body's defense.

🎯 Exam Tip: The primary function of the pineal gland is circadian rhythm regulation through melatonin secretion, but also list its other diverse roles.

 

Question 26. What are the other names of Luteotropic hormone?
Answer: Luteotropic hormone has several other names. These include prolactin, lactogenic hormone, and mammotropin. All these names refer to the same hormone that primarily supports lactation and milk production in females. It is important to know these alternative names as they are often used interchangeably.
In simple words: Luteotropic hormone is also known as prolactin, lactogenic hormone, or mammotropin.

🎯 Exam Tip: Be familiar with synonyms for hormones, as questions might use different terms for the same substance.

 

Question 27. Name the hormones that their secretions are regulated by negative feed back mechanisms?
Answer: The secretions of Thyroid Stimulating Hormone (TSH), also known as thyrotropin, and Adrenocorticotropic Hormone (ACTH) are regulated by negative feedback mechanisms. This means that when the levels of the hormones they stimulate (like thyroid hormones or cortisol) become high, they send a signal back to the pituitary or hypothalamus to reduce further release of TSH or ACTH. This ensures proper balance in the body.
In simple words: TSH (thyroid-stimulating hormone) and ACTH (adreno corticotropic hormone) are controlled by a negative feedback system to keep hormone levels balanced.

🎯 Exam Tip: Negative feedback is a common regulatory mechanism in the endocrine system, ensuring that hormone levels stay within a narrow, healthy range.

 

Question 28. Give the meanings of the word pituitary oxytocin and Hormone?
Answer:

1. Pituitary: This word means "to grow under."
2. Oxytocin: This word means "quick birth."
3. Hormone: This word means "to excite."

Understanding these original meanings helps to remember the functions of these substances.
In simple words: Pituitary means "to grow under," oxytocin means "quick birth," and hormone means "to excite."

🎯 Exam Tip: Knowing the etymology (origin of words) can sometimes provide clues about the function of a gland or hormone.

 

Question 29. Mention the importance of Luteotropic hormone in females?
Answer: Luteotropic hormone, also known as prolactin, is very important for females as it stimulates milk secretion after childbirth. This hormone ensures that a mother can produce enough milk to feed her baby. Without it, lactation would not be possible.
In simple words: Luteotropic hormone (prolactin) is important for women because it helps them make milk after giving birth.

🎯 Exam Tip: The main function of luteotropic hormone in females is directly related to lactation, so emphasize milk secretion.

 

Question 30. Why prolactin is called luteotropic hormone?
Answer: Prolactin is also called luteotropic hormone because it causes the corpus luteum in the ovary to develop and stay active. The corpus luteum then produces progesterone, which is essential for maintaining early pregnancy. Additionally, prolactin stimulates milk production during lactation, another key role.
In simple words: Prolactin is called luteotropic because it helps the corpus luteum grow, which is important for making hormones. It also helps with milk production.

🎯 Exam Tip: Connect prolactin's action on the corpus luteum with its role in maintaining progesterone levels, especially in the early stages of pregnancy.

 

Question 31. Point out the role of oxytocin in females?
Answer: In females, oxytocin plays two critical roles. First, it causes strong contractions of the smooth muscles in the uterus during childbirth, helping to deliver the baby. Second, it stimulates the ejection of milk from the mammary glands after birth, which is essential for breastfeeding. This hormone is sometimes called the "love hormone" due to its role in social bonding.
In simple words: In women, oxytocin causes the uterus to contract during childbirth and helps release milk from the breasts for feeding.

🎯 Exam Tip: Remember the "push and flow" actions of oxytocin: uterine contractions for birth and milk ejection for lactation.

 

Question 32. Name the hormones that play a key role in milk secretion?
Answer: The hormones that play a key role in milk secretion are prolactin (also known as lactogenic hormone or mammotropin or luteotropic hormone) and oxytocin. Prolactin is responsible for the production of milk, while oxytocin causes the milk to be released or ejected from the mammary glands. Both are essential for successful breastfeeding.
In simple words: Prolactin and oxytocin are the main hormones that help make and release milk.

🎯 Exam Tip: Differentiate between the *production* of milk (prolactin) and the *ejection* of milk (oxytocin).

 

Question 33. Name the hormone of pituitary that act on bloodvessels?
Answer: Vasopressin, a hormone from the pituitary, acts on blood vessels. When released in large amounts, it causes blood vessels to constrict, which in turn increases blood pressure. This function is important for maintaining blood volume and pressure, especially during dehydration or blood loss.
In simple words: Vasopressin from the pituitary gland makes blood vessels squeeze, which raises blood pressure.

🎯 Exam Tip: Vasopressin is also known as Anti-Diuretic Hormone (ADH), and its role in blood pressure regulation is secondary to its water reabsorption function.

 

Question 34. Which gland is located behind the third ventricle of brain?
Answer: The pineal gland is located behind the third ventricle of the brain. It is also known as the epiphysis cerebri or conarium. This small endocrine gland is responsible for producing melatonin, which is important for regulating sleep patterns. Its deep location within the brain highlights its protective placement.
In simple words: The pineal gland, also called epiphysis cerebri, is found behind the third ventricle of the brain.

🎯 Exam Tip: Accurately locating glands is essential. The pineal gland's position is a key identifying feature.

 

Question 35. Which is the largest endocrine in the body and where it is located?
Answer: The thyroid gland is the largest endocrine gland in the human body. It is a butterfly-shaped gland located in the neck, just below the larynx (voice box), and wraps around the trachea (windpipe). It has two lobes, one on each side of the trachea. This gland is vital for regulating metabolism.
In simple words: The thyroid gland is the biggest endocrine gland. It is located in the neck, below the voice box, on both sides of the windpipe.

🎯 Exam Tip: When identifying glands, always mention both its name and its precise location in the body for full clarity.

 

Question 36. Name the hormones secreted by thyroid gland.
Answer: The thyroid gland secretes three main hormones. These are Tri-iodothyronine (T3), Tetra-iodothyronine (T4 or Thyroxine), and Thyrocalcitonin. T3 and T4 are crucial for regulating metabolism, while thyrocalcitonin helps manage calcium levels in the blood. They play a vital role in overall body function.
In simple words: The thyroid gland makes T3, T4 (thyroxine), and thyrocalcitonin.

🎯 Exam Tip: Listing all three major thyroid hormones and understanding their primary roles is important for a comprehensive answer.

 

Question 37. What are parafollicular cells or 'C' cells?
Answer: Parafollicular cells, also known as 'C' cells, are specialized cells found within the thyroid gland. These cells are distinct from the follicular cells that produce thyroid hormones. Their main function is to secrete a hormone called thyrocalcitonin, which helps to lower blood calcium levels. They are crucial for maintaining calcium balance in the body.
In simple words: Parafollicular cells, or 'C' cells, are in the thyroid gland and make thyrocalcitonin, which lowers calcium in the blood.

🎯 Exam Tip: Differentiate 'C' cells from follicular cells; 'C' cells secrete calcitonin, while follicular cells produce T3 and T4.

 

Question 38. What element is important for synthesis of thyroid hormones? In what quantity it is essential?
Answer: Iodine is an essential element for the normal creation of thyroid hormones. A small amount of iodine, specifically about 1 milligram per week, is required for the thyroid gland to function properly. Without enough iodine, the body cannot produce adequate thyroid hormones, leading to various health issues.
In simple words: Iodine is needed to make thyroid hormones. We need about 1 mg of iodine each week.

🎯 Exam Tip: Emphasize both the specific element (iodine) and its approximate required quantity, as both are key pieces of information.

 

Question 39. Mention the normal glucose level in prepandial and postpandial test for glucose?
Answer:

1. Pre-prandial (Fasting): The normal glucose level before a meal is usually between 70-100 mg/dl.
2. Post-prandial (About 2 hours after food): The normal glucose level about two hours after eating is typically between 110-140 mg/dl.

These levels help doctors understand how well the body manages blood sugar.
In simple words: Before eating, normal blood sugar is 70-100 mg/dl. Two hours after eating, it should be 110-140 mg/dl.

🎯 Exam Tip: Remember the two key reference points (fasting and post-meal) and their respective normal ranges for glucose levels.

 

Question 40. Is it advisable to take alcohol frequently? What ill effects does it cause over the body?
Answer: No, it is not advisable to consume alcohol frequently due to its many harmful effects on the body. Alcohol consumption significantly impacts the endocrine system and disrupts the regulation of blood glucose levels. Furthermore, it can lower testosterone levels and increase the risk of osteoporosis, which weakens bones. These effects highlight the importance of moderation or avoidance.
In simple words: No, frequent alcohol use is bad. It harms the body's hormone system, raises blood sugar, lowers testosterone, and increases bone problems.

🎯 Exam Tip: Focus on alcohol's impact on the endocrine system (glucose regulation, testosterone) and bone health as key negative effects.

 

Question 41. What is the injection administered to diabetic patients? Why is it given as injection and not as oral pills?
Answer: Humulin-N, which is a type of human insulin, is administered to diabetic patients as an injection. It is given as an injection and not as an oral pill because insulin is a protein hormone. If taken orally, the digestive enzymes in the stomach and intestines would break it down, making it ineffective. Injecting it directly ensures it enters the bloodstream intact and can regulate blood sugar. Insulin is crucial for managing diabetes by helping cells absorb glucose.
In simple words: Diabetic patients get insulin shots because if they take it as a pill, their stomach acids will destroy the insulin, making it not work.

🎯 Exam Tip: The key reason for insulin injection is its protein nature, which would be degraded by digestive enzymes if taken orally.

 

Question 42. What is sporadic goiter?
Answer: Sporadic goiter is a genetic disease, meaning it is inherited and runs in families. Unlike endemic goiter, it is not caused by a deficiency of iodine or thyroxine in the diet. Instead, it arises from other factors, often genetic mutations, that affect thyroid hormone production. This condition leads to an enlarged thyroid gland without the common dietary causes.
In simple words: Sporadic goiter is a genetic disease, not caused by a lack of iodine.

🎯 Exam Tip: Differentiate sporadic goiter (genetic, not iodine-deficient) from endemic goiter (due to iodine deficiency) to avoid confusion.

 

Question 43. Why laughing is good for health?
Answer: Laughing is beneficial for health because it helps reduce the secretion of stress hormones like adrenaline. By lowering these stress hormones, laughter promotes relaxation in the body. This calming effect can improve overall well-being and help manage daily stressors more effectively. It is a natural way for the body to de-stress and feel better.
In simple words: Laughing is good because it lowers stress hormones like adrenaline and helps us relax.

🎯 Exam Tip: Connect the emotional action of laughing to a specific physiological effect (reduction of stress hormones) for a clear answer.

 

Question 44. Define circadian rhythm.
Answer: Circadian rhythm refers to the body's natural 24-hour cycle of biological activities. This cycle is linked to the natural periods of light and darkness. Examples include the sleep-wake cycle, changes in body temperature throughout the day, and fluctuations in appetite. The pineal gland plays a key role in regulating this rhythm through melatonin secretion.
In simple words: Circadian rhythm is our body's natural 24-hour cycle of activities, like sleeping and waking, that follows day and night.

🎯 Exam Tip: Define "circadian rhythm" by mentioning its 24-hour cycle, light/dark dependence, and providing relevant examples.

 

III. Short Answer

 

Question 1. What is simple goiter? What are its symptoms?
Answer: Simple goiter, also known as endemic goiter, is a condition where the thyroid gland enlarges. It happens because of insufficient secretion of thyroxine, often due to a lack of iodine in the diet. The main symptoms include an enlarged thyroid gland, a decrease in thyroxine levels in the blood, and an increase in TSH (Thyroid-Stimulating Hormone) secretion from the pituitary gland trying to stimulate the underactive thyroid. A visible swelling in the neck is a common sign.
In simple words: Simple goiter is an enlarged thyroid gland, caused by low thyroxine. Symptoms are a swollen neck, low thyroxine, and high TSH.

🎯 Exam Tip: When describing simple goiter, highlight the cause (hyposecretion of thyroxine, often iodine deficiency) and its visible symptom (enlarged thyroid).

 

Question 2. What is tetany?
Answer: Tetany is a condition caused by the insufficient secretion of parathyroid hormones, leading to very low calcium levels and increased phosphate levels in the blood. This imbalance results in symptoms such as muscle convulsions, jaw locking, increased heart rate, elevated body temperature, and severe muscular spasms. It is a serious condition that affects muscle and nerve function.
In simple words: Tetany happens when parathyroid hormones are low, causing low calcium and high phosphate. This leads to muscle cramps, jaw locking, and a fast heartbeat.

🎯 Exam Tip: Connect tetany directly to hyposecretion of parathyroid hormone, which in turn causes hypocalcemia (low blood calcium).

 

Question 3. What is Cushing's syndrome? What are its symptoms?
Answer: Cushing's syndrome is a disorder caused by the excessive secretion of cortisol from the adrenal cortex. This leads to several distinct symptoms. These include obesity, particularly in the face (often described as "moon face") and trunk, a red appearance on the face, hands, and feet, thick skin, excessive hair growth, loss of minerals from bones, and high blood pressure (systolic hypertension). These combined symptoms result from prolonged exposure to high cortisol levels.
In simple words: Cushing's syndrome is caused by too much cortisol. Symptoms include fat face and body, red skin, thick skin, lots of hair, weak bones, and high blood pressure.

🎯 Exam Tip: When listing symptoms of Cushing's syndrome, focus on the characteristic physical changes like facial obesity and skin issues, along with metabolic effects.

 

Question 4. What is the cause of dwarfism?
Answer: Dwarfism is typically caused by the insufficient secretion of growth hormone, especially during childhood. When growth hormone levels are too low, skeletal growth is slowed down or completely stopped, and sexual maturity may also be delayed. Children with dwarfism usually reach a maximum adult height of about 4 feet. This hormone deficiency impacts overall physical development.
In simple words: Dwarfism is caused by too little growth hormone in children, which stops bone growth and delays sexual development, leading to a very short height.

🎯 Exam Tip: Clearly state the cause (hypo-secretion of growth hormone in children) and the primary effect (stunted skeletal growth).

 

Question 5. What is Gigantism?
Answer: Gigantism is a condition resulting from the excessive secretion of growth hormone in children, before their growth plates have closed. This leads to an overgrowth of the skeleton, causing individuals to grow to an abnormal height, often up to 8 feet or more. While the bones grow excessively, the internal organs might not grow proportionally, which can lead to other health issues. It is essentially an extreme increase in body size.
In simple words: Gigantism is when children make too much growth hormone, causing them to grow extremely tall, sometimes over 8 feet.

🎯 Exam Tip: Differentiate gigantism (excess GH in childhood) from acromegaly (excess GH in adulthood), as both involve GH but have different effects due to the timing of onset.

 

Question 6. You are walking on the road, suddenly a man with a knife in his hand comes in front of you. What would be your reaction?
Answer: In such a dangerous situation, my body would react instantly due to the surge of adrenaline (also known as the "fight or flight" hormone). This hormone would cause physiological changes like increased heart rate, heightened senses, and redirection of blood flow to muscles. I would experience an immediate feeling of fear and a strong urge to either run away to safety or prepare to defend myself. The adrenaline provides a burst of energy needed for such an emergency. This natural response is vital for survival.
In simple words: My body would get a rush of adrenaline, making me very scared and giving me energy to either run away or fight to protect myself.

🎯 Exam Tip: When describing emergency responses, link the situation to the release of adrenaline and its physiological effects, such as increased heart rate and energy for "fight or flight."

 

Question 7. Why oxytocin is considered as quick or rapid birth?
Answer: Oxytocin is called the "quick or rapid birth" hormone because it strongly stimulates the contraction of the smooth muscles in the uterus during childbirth. These contractions are essential for pushing the fetus out of the mother's body. By intensifying and coordinating these contractions, oxytocin helps speed up the birthing process. It ensures an efficient and timely delivery.
In simple words: Oxytocin helps push the baby out quickly by making the uterus muscles contract strongly during childbirth.

🎯 Exam Tip: Focus on oxytocin's direct action on uterine smooth muscle contractions to explain its role in rapid birth.

 

Question 8. Why thymus is considered as a lymphoid organ?
Answer: The thymus is considered a lymphoid organ because it is crucial for the development and maturation of T-lymphocytes (T cells). These T cells, which originate in the bone marrow, travel to the thymus to "learn" to become immunologically competent. Once educated, they are able to identify and fight off infections and diseases, providing cell-mediated immunity. Thus, the thymus is central to the body's immune defense system.
In simple words: The thymus is a lymphoid organ because it trains T-lymphocytes to fight infections and provides immunity for the body.

🎯 Exam Tip: Highlight the role of the thymus in T-lymphocyte maturation and its contribution to cell-mediated immunity.

 

Question 9. Why is gluco corticoids considered in the life saving activity?
Answer: Glucocorticoids are considered "life-saving" hormones because they play a vital role during emergencies. In stressful situations, they stimulate the body to produce glucose from non-carbohydrate sources like lipids (fats) and proteins through processes called lipolysis and proteolysis. This releases energy, which is crucial for the body to respond to the emergency. They help the body cope with severe stress and maintain essential functions.
In simple words: Glucocorticoids are life-saving because they help the body get energy from fat and protein during emergencies.

🎯 Exam Tip: Emphasize the role of glucocorticoids in providing energy (glucose from fats/proteins) during stress, which is essential for survival.

 

Question 10. Why cortisol works as a stress combat hormone?
Answer: Cortisol is known as a stress combat hormone because it helps the body manage and respond to stress. It supports various functions, including maintaining cardiovascular health and kidney function. Cortisol also has anti-inflammatory effects and can suppress the immune response, which is important during stress. Additionally, it stimulates the production of red blood cells. These combined actions help the body cope with stressful conditions and adapt to changes. Its ability to regulate blood pressure and glucose is vital during stress.
In simple words: Cortisol helps us fight stress by maintaining heart and kidney health, reducing swelling, and boosting red blood cell production.

🎯 Exam Tip: Detail cortisol's multiple roles in stress response: cardiovascular support, anti-inflammatory action, immune modulation, and RBC production.

 

Question 11. How do the hormones act in the target tissue?
Answer: Hormones act on target tissues by traveling through the bloodstream as chemical signals. Once they reach a target organ, they bind to specific receptor molecules, which can be either on the cell surface or inside the cell. This binding triggers a response that can either speed up, slow down, or change the activity of the target cells. Hormones do not stay in the blood permanently; after their function, they are converted by the liver into inactive compounds and then excreted by the kidneys. This ensures their effects are regulated and temporary. The precise fit between hormone and receptor ensures the right tissue responds.
In simple words: Hormones travel in the blood, bind to special spots (receptors) on target cells, and then change how those cells work. The liver later breaks down the hormones for removal.

🎯 Exam Tip: Explain the hormone-receptor interaction and the eventual breakdown and excretion of hormones, highlighting the transient nature of their action.

 

Question 12. What is a limbic system?
Answer: The limbic system is a group of special structures located in the middle part of the brain. It is also sometimes called the "paleo mammalian brain" because it is an older part of our brain's evolutionary development. This system controls various important functions, including emotions, behavior, motivation, long-term memory, and the sense of smell (olfaction). It plays a crucial role in how we react to the world and form memories.
In simple words: The limbic system is a group of brain parts that control emotions, behavior, motivation, memory, and smell.

🎯 Exam Tip: Remember the limbic system's primary functions: emotions, memory, and motivation, and its location in the midbrain.

 

Question 13. What are exocrine glands? Give examples
Answer: Exocrine glands have special tubes called ducts. These ducts carry their secretions to specific surfaces, like the skin or the inside of the digestive tract. These glands release substances such as enzymes, saliva, and sweat. For example, salivary glands and gastric glands are exocrine glands.
In simple words: Exocrine glands send their products through tubes to a specific spot. Think of sweat glands or glands that make saliva.

🎯 Exam Tip: Remember that exocrine glands release their substances via ducts, unlike endocrine glands which release hormones directly into the bloodstream.

 

Question 14. Write down the functions of hypothalamus.
Answer: The hypothalamus performs several key functions in the body, connecting both the nervous and endocrine systems. It produces hypothalamic hormones that control the anterior pituitary gland, which is essential for many bodily processes. It also generates nerve signals that regulate the posterior pituitary gland's secretions. The hypothalamus helps maintain the body's stable internal environment, a process called homeostasis. It plays a role in regulating blood pressure, body temperature, heart function, and fluid and electrolyte balance, and even influences emotional responses. It also contains special neurosecretory cells that create neurotransmitters, which further manage pituitary gland secretions.
In simple words: The hypothalamus is like the body's control center. It makes hormones that tell the pituitary gland what to do, keeps our body steady (like temperature and blood pressure), and helps with our emotions.

🎯 Exam Tip: When listing functions of the hypothalamus, focus on its role as a bridge between the nervous and endocrine systems and its impact on homeostasis.

 

Question 15. Draw the diagram of the hypothalamus and pituitary gland and label the following parts.
A. Anterior lobe
B. Posterior lobe
C. Hypothalamus
D. Interior Hypophyseal artery
Answer:

In simple words: The diagram shows the brain's hypothalamus and pituitary gland, which work closely together. The hypothalamus is above, and the pituitary gland (with its front and back parts) hangs below it, connected by a stalk. An artery supplies blood to this important connection.

🎯 Exam Tip: When drawing, clearly distinguish the anterior and posterior lobes of the pituitary and show their connection to the hypothalamus. Accurate labeling is key for full marks.

 

Question 16. Draw the diagram of thyroid gland and label the following parts
A Thyroid cartilage
B. Thyroid gland
C. Trachea
D.Isthmus
Answer:

In simple words: This picture shows the thyroid gland, which is shaped like a butterfly. It sits in front of your windpipe (trachea) in your neck. The thyroid cartilage is a part of your voice box above it. A narrow band of tissue, called the isthmus, connects the two sides of the thyroid gland.

🎯 Exam Tip: Clearly draw the butterfly shape of the thyroid gland and its position relative to the trachea. The isthmus connecting the lobes is an important detail to include.

 

Question 17. Draw the diagram of thyroid gland and label the following parts
A. Capsule
B. Cortex
C. Medulla
D. Blood Vessels
Answer: (Note: The labels provided refer to an adrenal gland, not a thyroid gland. The diagram below represents an adrenal gland with the requested parts.)

In simple words: This diagram shows an adrenal gland. The outermost layer is the capsule. Just inside is the cortex, and at the very center is the medulla. Blood vessels run through the gland to supply it with blood and carry hormones away.

🎯 Exam Tip: Focus on accurately representing the distinct layers: the outer capsule, the cortex, and the central medulla, as these are critical structural components of the adrenal gland.

 

Question 18. Explain the role of luteinizing hormone (LH) in male and females.
Answer: Luteinizing Hormone (LH) is a glycoprotein hormone that plays a crucial role in reproduction in both males and females. In males, it is also known as Interstitial Cell Stimulating Hormone (ICSH). ICSH acts on the Leydig cells (interstitial cells) in the testes, causing them to produce the male sex hormone, testosterone. In females, LH works with Follicle Stimulating Hormone (FSH) to help ovarian follicles mature. LH also triggers ovulation, which is the release of an egg from the ovary. After ovulation, LH helps maintain the corpus luteum, a structure that forms in the ovary, and promotes the creation and release of other ovarian hormones. The secretion of both FSH and LH begins during puberty. These hormones are collectively known as gonadotropins.
In simple words: LH is a hormone important for having babies. In boys, it helps make testosterone. In girls, it helps release eggs and makes other female hormones.

🎯 Exam Tip: Remember to differentiate LH's specific actions in males (testosterone production by Leydig cells) and females (ovulation and corpus luteum maintenance), as this is a key distinction.

 

Question 19. Compare the structural difference of vasopressin and oxytocin. Vasopressin Oxytocin
Answer: Vasopressin and oxytocin are both peptide hormones, meaning they are made of amino acids. Both are composed of amino acids. However, they differ in their specific amino acid sequence. Vasopressin's amino acid sequence is cysteine-tyrosine-phenylalanine-glutamine-asparagine-cysteine-proline-arginine-glycine. Oxytocin's amino acid sequence is cysteine-tyrosine-isoleucine-glutamine-asparagine-cysteine-proline-leucine-glycine. The difference lies in two amino acids: phenylalanine and arginine in vasopressin are replaced by isoleucine and leucine in oxytocin. This small change makes them have very different jobs in the body.
In simple words: Both vasopressin and oxytocin are small protein hormones. They are almost identical, but just two tiny parts (amino acids) are different, which makes them work in different ways in the body.

🎯 Exam Tip: When comparing peptide hormones like vasopressin and oxytocin, knowing that they are both amino acid chains but differ by a few specific amino acids is crucial.

 

Question 20. How does the posterior lobe of the pituitary help in osmoregulation?
Answer: The posterior lobe of the pituitary gland plays a key role in osmoregulation, which is how the body controls its water balance. It does this by releasing Antidiuretic Hormone (ADH), also known as vasopressin, a peptide hormone. ADH promotes the reabsorption of water and electrolytes by the distal tubules of the nephron in the kidneys, reducing water loss through urine. This means the body saves water, so ADH is also called an anti-diuretic hormone. When there isn't enough ADH, a condition called Diabetes Insipidus occurs, causing the body to produce large amounts of urine. This hormone also helps in osmoregulation by, when released in large amounts, causing blood vessels to constrict, which increases blood pressure. So, ADH helps keep the right amount of water in the body and also helps manage blood pressure.
In simple words: The back part of the pituitary gland releases ADH hormone. This hormone tells the kidneys to keep more water in the body, so we don't pee too much. This helps keep our body's water level balanced.

🎯 Exam Tip: Connect ADH directly to water reabsorption in the kidneys and link its deficiency to Diabetes Insipidus for a complete answer.

 

Question 21. Explain the role of melatonin in our body.
Answer: Melatonin is a hormone secreted by the pineal gland, which is located in the brain. It plays a central role in regulating the body's circadian rhythm, which is our natural sleep-wake cycle. Melatonin helps us maintain normal sleep patterns. It also influences the timing of sexual maturation of the gonads. Additionally, melatonin affects metabolism, skin pigmentation, the menstrual cycle in females, and the body's defense mechanisms. It acts like an internal clock, helping our body respond to natural light and darkness.
In simple words: Melatonin is a hormone from the pineal gland. It helps us sleep and wake up at the right times, controls some body functions, and affects skin color and our body's defenses.

🎯 Exam Tip: The primary role of melatonin is circadian rhythm regulation (sleep-wake cycle); also mention its influence on sexual maturation and pigmentation for a comprehensive answer.

 

Question 22. List out the role of thyroxine or tetra iodo thyronine (T4) in our body.
Answer: Thyroxine, also known as tetraiodothyronine (T4), is a crucial hormone in our body with multiple roles. It regulates the Basal Metabolic Rate (BMR) and heat production, essentially controlling how fast our body uses energy. It stimulates protein synthesis and promotes overall growth, which is vital for the development of the skeletal and nervous systems. Thyroxine also helps maintain blood pressure and reduces serum cholesterol levels. To ensure proper reproductive health, optimum levels of thyroxine are necessary for healthy gonadal functions. This hormone ensures many body systems work correctly, impacting energy, growth, and overall well-being.
In simple words: Thyroxine (T4) helps control our body's energy use, growth, and how warm we feel. It also keeps our bones and nerves healthy, helps control blood pressure, and lowers bad cholesterol.

🎯 Exam Tip: Remember that thyroxine (T4) primarily controls the body's metabolic rate and is essential for growth and development, especially of the nervous system.

 

Question 23. Which hormone is called hypercalcemic hormone? Explain its role.
Answer: The parathyroid hormone (PTH) is called the hypercalcemic hormone. It is a peptide hormone. PTH plays a critical role in controlling calcium and phosphate levels in the blood, which is known as calcium and phosphate homeostasis. Its secretion is regulated by the calcium level in the blood itself. PTH increases blood calcium levels by stimulating osteoclasts, which are cells that dissolve bone matrix, releasing calcium and phosphate into the blood. It also enhances the re-absorption of calcium by the renal tubules in the kidneys and promotes the excretion of phosphates. Furthermore, PTH activates vitamin D, which then increases calcium absorption in the intestinal mucosal cells. This complete action raises blood calcium levels.
In simple words: Parathyroid hormone (PTH) is called the hypercalcemic hormone because it raises the amount of calcium in the blood. It makes our bones release calcium and helps our body take in more calcium from food, keeping our calcium levels healthy.

🎯 Exam Tip: Clearly state that parathyroid hormone (PTH) increases blood calcium levels, making it the hypercalcemic hormone, and mention its action on bones, kidneys, and intestines.

 

Question 24. Explain the role of heart as a partial endocrine gland.
Answer: The heart acts as a partial endocrine gland by secreting a very important peptide hormone. In the heart, specialized cells called cardiocytes, located in the atrial walls, produce Atrial Natriuretic Factor (ANF). When blood pressure rises, ANF is released into the bloodstream. This hormone then causes blood vessels to dilate, or widen, which helps to reduce high blood pressure. In this way, the heart contributes to the body's hormonal regulation of blood pressure, demonstrating its role beyond just pumping blood.
In simple words: The heart is not just a pump; it's also a gland that makes a hormone called ANF. When blood pressure goes up, ANF is released, which helps to lower the blood pressure by relaxing blood vessels.

🎯 Exam Tip: The key point is that the heart secretes ANF when blood pressure is high, leading to blood vessel dilation and reduced pressure.

 

Question 25. Is it good to take synthetic soft drinks? Why?
Answer: No, it is generally not good to consume synthetic soft drinks frequently. These drinks can have several negative effects on the body. Firstly, many branded soft drinks can damage our endocrine system, which controls hormones. When soft drinks are consumed, the high sugar content rapidly increases blood glucose levels, leading to an elevated secretion of insulin. While insulin initially tries to reduce these high glucose levels, consistently high insulin levels can diminish overall immunity. Furthermore, frequent consumption of soft drinks is associated with health issues like obesity and various cardiovascular disorders. They are not good for long-term health.
In simple words: No, synthetic soft drinks are not good. They can hurt our hormone system, cause high sugar levels, lower our body's defense against illness, and lead to problems like being overweight and heart issues.

🎯 Exam Tip: Highlight the direct impacts of synthetic soft drinks on blood sugar regulation, the endocrine system, and long-term health risks like obesity and heart problems.

 

Question 26. The doctors avoid prescribing steroid tablets most often. Why?
Answer: Doctors often avoid prescribing steroid tablets for long-term use because their misuse or prolonged use can lead to several serious health problems. These include high blood pressure, various heart diseases, and liver damage. Steroids can also increase the risk of cancer, stroke, and blood clots. Additionally, they have several unpleasant side effects such as nausea, vomiting, ligament and tendon injuries, headaches, joint pain, muscle cramps, diarrhea, and sleep problems. Due to these potential severe side effects, steroids are typically prescribed with caution and for limited durations.
In simple words: Doctors don't like giving steroid pills often because they can cause serious health problems like high blood pressure, heart issues, liver damage, and even cancer. They also have many bad side effects, so they are only used when really necessary and for a short time.

🎯 Exam Tip: Focus on the significant health risks associated with steroid abuse, such as cardiovascular issues, organ damage, and metabolic disturbances.

 

Question 27. if para-thyroid gland shows hyper-secretion. What will be the symptoms of this disorder?
Answer: If the parathyroid gland shows hyper-secretion, it leads to a disorder called hyperparathyroidism. This condition is caused by an excessive release of parathyroid hormone (PTH) into the blood. The primary symptoms of hyperparathyroidism are demineralization of bones, meaning the bones lose their mineral content and become weaker. This can also lead to the formation of cysts in the bones, which are fluid-filled sacs. Other symptoms include softening of the bone, general weakness, and renal disorders due to altered calcium and phosphate levels. Essentially, the bones become fragile, and the body's mineral balance is severely disrupted.
In simple words: Too much parathyroid hormone causes hyperparathyroidism. This makes bones lose minerals, become soft, form cysts, and leads to general weakness and kidney problems.

🎯 Exam Tip: The main symptom of hyperparathyroidism is demineralization and softening of bones, caused by excess PTH pulling calcium from bone into the blood.

 

Question 28. Differentiate Glycogenolysis from gluconeogenesis.
Answer: Glycogenolysis and gluconeogenesis are two different processes involved in glucose metabolism, both of which increase blood glucose levels. Glycogenolysis is the breakdown of glycogen into glucose. This process primarily occurs in the liver and is stimulated by the hormone glucagon, which releases glucose from liver cells to raise blood glucose levels. On the other hand, gluconeogenesis is the synthesis of new glucose from non-carbohydrate sources, such as lactic acid and amino acids. This process also happens mainly in the liver and is important for maintaining blood glucose when carbohydrate intake is low. Both processes ultimately aim to increase the availability of glucose in the bloodstream.
In simple words: Glycogenolysis is when the body breaks down stored sugar (glycogen) into usable sugar (glucose). Gluconeogenesis is when the body makes new sugar from things that aren't sugar, like fats or proteins. Both help raise blood sugar.

🎯 Exam Tip: Remember that glycogenolysis breaks down existing glycogen stores, while gluconeogenesis creates new glucose from non-carbohydrate precursors. Both are crucial for maintaining blood glucose.

 

Question 29. Mention the symptoms of diabetes mellitus.
Answer: Diabetes mellitus is a condition characterized by elevated blood glucose levels. The primary symptoms include polyuria, which is excessive urination, as the kidneys try to remove excess glucose. Polyphagia, or excessive intake of food, occurs because cells can't get enough glucose for energy, making the person feel constantly hungry. Polydipsia, meaning excessive consumption of liquids due to thirst, is also common as the body tries to compensate for fluid loss from increased urination. Another significant symptom is ketosis, which is the breakdown of fat into ketone bodies that accumulate in the blood, often due to a lack of insulin to utilize glucose. Gluconeogenesis, the conversion of non-carbohydrates into glucose, also occurs more in diabetes, worsening the high blood sugar.
In simple words: Diabetes mellitus makes people pee and drink a lot, feel very hungry, and break down fat for energy, leading to high sugar in their blood.

🎯 Exam Tip: Key symptoms of diabetes mellitus are the "3 Ps": Polyuria (excessive urination), Polydipsia (excessive thirst), and Polyphagia (excessive hunger), along with ketosis.

 

Question 30. Give a short account on hypothalamus.
Answer: The hypothalamus is a small, cone-shaped structure located in the brain that extends downward into the pituitary stalk. It serves as a vital link between the nervous system and the endocrine system. The hypothalamus controls the pituitary gland and produces neurotransmitters that act as either releasing or inhibitory hormones. It contains groups of neurosecretory cells that synthesize and release these neurotransmitters, regulating the pituitary gland's secretions. This region is critical for maintaining homeostasis, controlling blood pressure, body temperature, heart function, and fluid and electrolyte balance, and influencing emotional responses. Essentially, it acts as the body's internal control center, ensuring balance and proper functioning across many systems.
In simple words: The hypothalamus is a small brain part that connects nerves and hormones. It controls the pituitary gland and keeps our body balanced, like managing temperature, blood pressure, and emotions.

🎯 Exam Tip: Emphasize the hypothalamus's dual role as a nervous and endocrine system link, and its central function in regulating homeostasis and pituitary gland activity.

 

Question 31. Comment on pineal gland.
Answer: The pineal gland is a small endocrine gland located deep within the brain, behind the third ventricle. It is also known as the epiphysis cerebri or conarium. This gland is composed of specialized parenchymal and interstitial cells. Its main function is to secrete the hormone melatonin, which plays a central role in regulating the body's circadian rhythm, or our natural sleep-wake cycle. The pineal gland helps maintain normal sleep patterns and influences the timing of sexual maturation of the gonads. Additionally, melatonin affects metabolism, skin pigmentation, the menstrual cycle, and the body's immune defense mechanisms. It acts as a biological clock, responding to light and darkness.
In simple words: The pineal gland is a small gland in the brain that makes melatonin. This hormone helps control our sleep patterns, affects body functions like metabolism and skin color, and helps with sexual development.

🎯 Exam Tip: Key points for the pineal gland are its secretion of melatonin and its role in regulating circadian rhythm (sleep-wake cycle).

 

Question 32. Write down the functions of thyrocalcitonin.
Answer: Thyrocalcitonin is a polypeptide hormone produced by the parafollicular or 'C' cells of the thyroid gland. Its primary function is to regulate blood calcium and phosphate levels. Specifically, thyrocalcitonin acts as a hypocalcemic hormone, meaning it reduces the blood calcium level. It achieves this by opposing the effects of parathyroid hormone (PTH). Thyrocalcitonin inhibits the activity of osteoclasts, the cells responsible for breaking down bone and releasing calcium. By preventing calcium from being withdrawn from the bones, it helps keep calcium in the skeletal structure and lowers its concentration in the blood. This balance is crucial for bone health and overall calcium homeostasis.
In simple words: Thyrocalcitonin is a hormone from the thyroid gland that lowers the amount of calcium in your blood. It does this by stopping your bones from releasing calcium, which helps keep your bones strong.

🎯 Exam Tip: Remember that thyrocalcitonin's main role is to lower blood calcium levels, making it a key antagonist to parathyroid hormone.

 

Question 33. Give a brief account on parathyroid gland.
Answer: In humans, there are typically four tiny parathyroid glands. These are located on the posterior, or back, surface of the thyroid glands in the neck. Each parathyroid gland is composed of two main types of cells: chief cells and oxyphil cells. The chief cells are responsible for secreting parathyroid hormone (PTH), which is crucial for calcium regulation. The specific functions of oxyphil cells are not yet fully understood. The parathyroid glands are essential for maintaining calcium and phosphate balance in the body, primarily through the action of PTH, which raises blood calcium levels.
In simple words: Parathyroid glands are small glands behind the thyroid. They have chief cells that make parathyroid hormone, which is important for controlling calcium in your blood. The job of the other cells (oxyphil cells) is not fully known.

🎯 Exam Tip: Key facts about parathyroid glands include their number (usually four), location (posterior to thyroid), and primary function (secretion of PTH for calcium regulation).

 

Question 34. Write short notes on thymus gland.
Answer: The thymus gland is a unique organ that functions as both a partial endocrine gland and a lymphoid organ. It is a bi-lobed structure situated just above the heart and behind the sternum (breastbone). The thymus is covered by a fibrous capsule. Anatomically, it is divided into an outer cortex and an inner medulla. This gland secretes several hormones, including thymulin, thymosin, thymopoietin, and thymic humoral factor (THF). The primary function of the thymus is the production and maturation of immune-competent T lymphocytes. These T lymphocytes are crucial for providing cell-mediated immunity, which is a vital part of the body's defense system against infections and diseases. The thymus is most active during childhood and begins to shrink after puberty.
In simple words: The thymus gland is located near the heart. It makes hormones and is important for our immune system, helping T cells grow and learn to fight off sickness. It is most active when we are young.

🎯 Exam Tip: The thymus gland's main function is the maturation of T lymphocytes, which are essential for cell-mediated immunity, making it a critical part of the immune system.

 

Question 35. Write about Acromegaly.
Answer: Acromegaly is a hormonal disorder that occurs in adults due to the excessive secretion of growth hormone (GH), typically after the growth plates in the bones have fused. Unlike gigantism, which occurs in children, acromegaly causes specific symptoms in adults. These symptoms include an overgrowth of bones in the hands, feet, and jaw, leading to noticeable enlargement. There can also be malfunctioning of the gonads, and a significant enlargement of internal organs, known as viscera. This includes the tongue, lungs, heart, liver, and spleen, as well as other endocrine glands like the thyroid and adrenal glands. The condition results in a distinct appearance and various health complications due to continuous tissue growth.
In simple words: Acromegaly is a condition in adults caused by too much growth hormone. It makes bones in the hands, feet, and jaw grow bigger, and also makes internal organs larger, changing a person's appearance and health.

🎯 Exam Tip: Differentiate acromegaly (excess GH in adults, causing bone and organ enlargement) from gigantism (excess GH in children, causing overall tall stature).

 

Question 36. What is hyperparathyroidism? Write down its symptoms.
Answer: Hyperparathyroidism is a condition caused by the excessive secretion of parathyroid hormone (PTH) in the blood. This leads to elevated calcium levels (hypercalcemia) and decreased phosphate levels in the blood. The symptoms of hyperparathyroidism include demineralization of bones, where minerals are pulled from the bone into the bloodstream, making the bones weak and prone to fractures. This can also lead to the formation of cysts in the bones and a general softening of bone tissue. Other symptoms include loss of muscle tone, muscular weakness, general weakness, and potential renal disorders due to the altered mineral balance. High calcium can also cause kidney stones and affect kidney function.
In simple words: Hyperparathyroidism means too much parathyroid hormone, which pulls calcium from bones. Symptoms include weak bones that can soften or form cysts, and a general feeling of weakness.

🎯 Exam Tip: Remember that hyperparathyroidism leads to weakened bones and potential bone cysts due to excessive calcium release from the skeletal system.

 

Question 37. Comment on Addison's disease.
Answer: Addison's disease is a serious endocrine disorder caused by the hyposecretion, or insufficient production, of glucocorticoids and mineralocorticoids from the adrenal cortex. This deficiency leads to a range of symptoms. These include muscular weakness, low blood pressure (hypotension), and loss of appetite, often accompanied by vomiting. A characteristic symptom is hyperpigmentation of the skin, where the skin develops a darker, bronzed appearance. Patients also experience a low metabolic rate, subnormal body temperature, reduced blood volume leading to weight loss, and low aldosterone levels. The low aldosterone further results in increased urinary excretion of sodium chloride and water, contributing to dehydration and electrolyte imbalance. It is a chronic condition that requires lifelong hormone replacement therapy.
In simple words: Addison's disease happens when the adrenal glands don't make enough hormones. This causes symptoms like muscle weakness, low blood pressure, dark skin, and weight loss, affecting many body functions.

🎯 Exam Tip: Key symptoms of Addison's disease are muscular weakness, low blood pressure, and distinctive hyperpigmentation of the skin, all resulting from adrenal hormone deficiency.

 

Question 38. Give reasons for Diabetes insipidus and point out its symptoms.
Answer: Diabetes insipidus is caused by the hyposecretion, or insufficient production, of vasopressin, also known as antidiuretic hormone (ADH). This hormone is normally secreted by the posterior lobe of the pituitary gland and helps the kidneys reabsorb water. When there isn't enough ADH, the kidneys are unable to conserve water effectively, leading to excessive water loss. The primary symptoms of diabetes insipidus are polyuria, which is very frequent and large amounts of urination, and polydipsia, an excessive consumption of liquids due to intense thirst. Patients constantly feel thirsty and need to drink a lot of water to replace the fluids lost through urine. Despite drinking, they often feel dehydrated because their body cannot retain enough water.
In simple words: Diabetes insipidus happens when the body doesn't make enough ADH hormone. This causes people to pee a lot and feel very thirsty, always needing to drink water.

🎯 Exam Tip: Distinguish Diabetes Insipidus (ADH deficiency, excessive urination and thirst, no sugar in urine) from Diabetes Mellitus (insulin deficiency/resistance, sugar in urine).

 

Question 39. Define BMR.
Answer: BMR stands for Basal Metabolic Rate. It is defined as the minimum amount of energy the body needs to keep functioning when it is at complete rest, both physically and mentally. This energy is used for essential life-sustaining activities such as breathing, blood circulation, maintaining body temperature, and cell production, without any added physical activity or digestion. It represents the calories burned when the body is doing absolutely nothing but staying alive. Factors like age, sex, weight, and thyroid hormone levels can influence a person's BMR.
In simple words: BMR is how much energy your body uses just to stay alive when you are resting completely, like for breathing and keeping warm.

🎯 Exam Tip: Remember that BMR refers to energy expenditure at absolute rest, covering only essential physiological functions.

 

Question 40. Write down the general function of adrenalin hormone and its nature of secretion?
Answer: Adrenalin, also known as epinephrine, is a hormone secreted by the adrenal medulla. Its general function is to prepare the brain and body for immediate action, especially during stressful or emergency situations. This response is commonly known as the 'fight or flight' response. The nature of its secretion varies: it is released in smaller amounts during sleep but increases significantly during wakefulness and reaches much higher levels during stress. Adrenalin increases heart rate, blood pressure, dilates air passages to improve breathing, and boosts glucose release for energy, all to help the body react quickly to perceived threats. Nor-adrenalin (norepinephrine) has similar effects, primarily mobilizing the brain and body for action.
In simple words: Adrenalin is an emergency hormone that makes your body ready to "fight or fly." It speeds up your heart, raises blood pressure, and gives you energy quickly when you are scared or stressed.

🎯 Exam Tip: The key function of adrenalin is to trigger the "fight or flight" response, mobilizing the body for rapid action in emergencies.

 

Question 41. Old age people are sick often why?
Answer: Older people often get sick more frequently because their immune system becomes weaker with age. This reduced immunity is largely due to the degeneration of the thymus gland. The thymus gland is vital during childhood for the maturation of T lymphocytes, which are essential immune cells. As people age, the thymus gland shrinks and becomes less active, leading to a decrease in the production and effectiveness of these T lymphocytes. Additionally, the level of thymosin, a hormone produced by the thymus, also decreases. This overall weakening of the immune system makes older individuals more vulnerable to infections, diseases, and slower recovery times, leading to them being sick more often.
In simple words: Older people get sick more often because their thymus gland, which makes important immune cells, gets weaker as they age. This means their body can't fight off sickness as well.

🎯 Exam Tip: Link the increased sickness in old age directly to the degeneration of the thymus gland and the resulting decline in immune function.

 

Question 42. What is the role of pars intermedia in mammals and in other vertebrates?
Answer: The role of pars intermedia, a part of the pituitary gland, differs between mammals and other vertebrates. In mammals, the pars intermedia is generally insignificant or very small, and its role is often considered negligible. However, in other vertebrates, such as amphibians, fish, and reptiles, the pars intermedia is much more developed and plays a crucial role. It secretes melanocyte-stimulating hormone (MSH). This MSH then induces pigmentation in the skin, helping these animals change color to adapt to their environment or for camouflage. For example, a chameleon can change its skin color due to the MSH from its pars intermedia. In mammals, these functions are often handled by other mechanisms or are less pronounced.
In simple words: In most mammals, the pars intermedia part of the pituitary gland doesn't do much. But in other animals like frogs or fish, it makes a hormone called MSH that helps them change their skin color.

🎯 Exam Tip: The key distinction is that pars intermedia is largely insignificant in mammals but crucial in other vertebrates for secreting MSH and regulating skin pigmentation.

 

IV. Brief Answers

 

Question 1. Describe the mechanism of peptide hormone action with a diagram.
Answer: Peptide hormones, which are water-soluble, cannot easily pass through the cell membrane because it is made of lipids. Therefore, they bind to specific receptor proteins located on the exterior surface of the target cell membrane. This binding acts as the first messenger. Once bound, the receptor activates a second messenger system inside the cell, often involving cyclic AMP (cAMP). This cAMP then regulates various cellular metabolic processes. The entire interaction, from hormone binding to cAMP activation, is known as a signaling cascade, which can amplify the initial signal significantly. These hormones are processed and transported by the Golgi apparatus, which acts as their site of modification. A single hormone molecule can bind to multiple receptor molecules, and each activated receptor generates more cAMP, leading to stronger signals and a wide-ranging cellular response. Ultimately, these hormones cause changes in cellular function without directly entering the cell.

In simple words: Peptide hormones cannot go inside cells because they are water-soluble. So, they stick to special parts (receptors) on the cell's outer wall. This sticking tells the cell to make a "second messenger" like cAMP. This messenger then goes inside and tells the cell what to do, like changing its activities.

🎯 Exam Tip: Highlight that peptide hormones use a "second messenger" system (like cAMP) because they cannot directly cross the cell membrane, which is a key difference from steroid hormones.

 

Question 2. Describe the mechanism of action of steroid hormone.
Answer: Steroid hormones are lipid-soluble, meaning they can easily pass through the lipid-based cell membrane. Once inside the cell, they bind to specific receptor proteins, which can be located either in the cytoplasm or the nucleus. This hormone-receptor complex then pairs up with another receptor to form a functional complex. This complex then moves into the nucleus and binds directly to specific regions on the DNA. This binding alters the transcription of certain genes, leading to changes in the production of messenger RNA (mRNA) and subsequently, specific proteins. These changes in protein synthesis lead to the long-lasting effects of steroid hormones. For example, estrogen works through this mechanism. Because they directly influence gene expression, their effects tend to be slower to start but last for a longer time compared to peptide hormones.

In simple words: Steroid hormones can pass right through the cell wall. Inside, they link up with a special receptor and then go into the cell's control center (nucleus). There, they tell the DNA what new proteins to make, changing how the cell works for a longer time.

🎯 Exam Tip: The key mechanism for steroid hormones is their ability to cross the cell membrane and directly interact with DNA in the nucleus to alter gene expression, leading to slower but more prolonged effects.

 

Question 3. What is typical about Addison's disease.
Answer: Addison's disease is a condition caused by the adrenal glands not making enough hormones, specifically glucocorticoids and mineralocorticoids. People with this disease often show symptoms like dark skin patches, feeling very weak, having low blood pressure, and losing their appetite. This means their body cannot handle stress well or keep salt and water balanced. One interesting fact about this disease is that it can slowly get worse over time if not treated.
In simple words: Addison's disease happens when adrenal glands do not make enough hormones, leading to symptoms like dark skin, weakness, and low blood pressure.

🎯 Exam Tip: Remember that Addison's disease is about *under*secretion of adrenal hormones, leading to a specific set of symptoms including hyperpigmentation.

 

Question 4. What is the cause of cretinism? What are the symptoms?
Answer: Cretinism is a condition caused by the thyroid gland not producing enough hormones (hypothyroidism) from birth or early childhood. This lack of thyroid hormones leads to several symptoms:

• Slowed bone growth, meaning the child will be much shorter than average.
• Delayed sexual development, so they do not mature physically at the normal age.
• Reduced mental ability and slower brain development.
• Skin changes like thick, wrinkled skin, a bloated face, and a large, protruding tongue.
• Other signs include a low body temperature, a slow heart rate (low BMR), and high cholesterol levels.

A healthy thyroid is crucial for proper growth and brain development during childhood.In simple words: Cretinism is caused by a lack of thyroid hormone in children, leading to slow growth, reduced intelligence, and specific changes in their appearance and body functions.

🎯 Exam Tip: When listing symptoms, group similar ones together for clarity and ensure you cover both physical and mental aspects of the disorder.

 

Question 5. What are the hormones responsible for maintaining blood glucose levels?
Answer: The main hormones responsible for keeping blood glucose (sugar) levels balanced are insulin and glucagon, both produced by the pancreas.
Insulin: This is a peptide hormone that helps lower blood glucose. It does this by telling body cells (especially muscle and fat cells) to take in glucose from the blood. Insulin also stops the liver from breaking down glycogen into glucose and prevents the body from turning amino acids or fats into glucose. Because it lowers blood sugar, insulin is called a hypoglycemic hormone. Without enough insulin, glucose stays in the blood, causing high blood sugar.
Glucagon: This is also a polypeptide hormone, but it does the opposite of insulin. Glucagon works on the liver to raise blood glucose levels. It makes the liver break down stored glycogen into glucose (this process is called glycogenolysis). It also helps the liver create new glucose from non-carbohydrate sources like lactic acid (this is called gluconeogenesis). Because it increases blood sugar, glucagon is a hyperglycemic hormone. When these two hormones work together, they keep your blood sugar at a healthy level.In simple words: Insulin lowers blood sugar by helping cells absorb glucose, while glucagon raises blood sugar by making the liver release stored glucose. Both are from the pancreas and work together to keep sugar levels balanced.

🎯 Exam Tip: Clearly differentiate between the opposing roles of insulin (lowers glucose) and glucagon (raises glucose) and name their site of production, the pancreas.

 

Question 6. What is an exophthalmic goiter? What are its symptoms?
Answer: An exophthalmic goiter is a condition caused by the thyroid gland producing too much thyroid hormone (hyperthyroidism). This leads to an overactive metabolism and a range of physical symptoms:

• The thyroid gland itself becomes noticeably larger.
• The body's basic metabolic rate (BMR) increases significantly.
• Breathing and waste removal rates become higher.
• The heart beats faster and blood pressure increases.
• Body temperature rises.
• The eyeballs may bulge out (exophthalmos), which is a key symptom unique to this type of goiter.
• Muscles may feel weak.
• Weight loss can occur despite normal or increased appetite.

It's important to understand that while simple goiter is often due to iodine deficiency, exophthalmic goiter is an autoimmune condition involving overactivity of the thyroid.In simple words: Exophthalmic goiter is when your thyroid gland makes too much hormone, causing symptoms like a bigger thyroid, fast heartbeat, feeling hot, and bulging eyes.

🎯 Exam Tip: Highlight "bulging eyeballs" (exophthalmos) as the distinctive symptom of exophthalmic goiter, differentiating it from simple goiter.

 

Question 7. What is meant by negative feedback mechanism? Explain with an example.
Answer: A negative feedback mechanism is a way the body regulates its internal environment by reversing any changes that happen. If a level of something (like a hormone) goes up, the body will work to bring it back down. If it goes down, the body will work to bring it back up. This helps maintain balance.
Example: Regulation of Thyroxine
When the level of thyroxine in the blood decreases, the hypothalamus in the brain senses this.
\( \implies \) The hypothalamus then releases a "thyroid releasing factor" (TRF).
\( \implies \) This TRF makes the pituitary gland secrete "thyroid stimulating hormone" (TSH).
\( \implies \) TSH then tells the thyroid gland to release more thyroxine into the blood.
When the thyroxine level in the blood increases, it is sensed by both the pituitary and hypothalamus.
\( \implies \) This increased thyroxine then acts to *inhibit* (stop) TSH secretion from the pituitary and TRF secretion from the hypothalamus. This whole process keeps thyroxine levels stable, acting like a thermostat for the body.In simple words: Negative feedback means the body tries to undo changes to keep things balanced. For example, if thyroxine goes down, the brain tells the thyroid to make more; if it goes up, the brain tells it to stop.

🎯 Exam Tip: When explaining negative feedback, use an arrow diagram or clear sequential steps to show how the initial change is detected and then reversed by the body.

 

Question 8. Why parathormone is considered as hypercalcemic hormone.
Answer: Parathormone (PTH), also known as parathyroid hormone, is called a hypercalcemic hormone because its main job is to increase the level of calcium in the blood. It does this by several actions:

• It makes osteoclasts (cells that break down bone) more active, which releases calcium and phosphate from the bone matrix into the blood.
• It helps the kidneys reabsorb more calcium back into the blood while making them excrete more phosphate.
• It helps activate Vitamin D, which then allows the intestines to absorb more calcium from food.

These combined actions directly raise blood calcium levels, which is why it's considered hypercalcemic. Maintaining proper calcium levels is vital for strong bones and nerve function.
In simple words: Parathormone is called a hypercalcemic hormone because it works to raise the amount of calcium in your blood by taking it from bones, kidneys, and food.

🎯 Exam Tip: List the three main ways parathormone increases blood calcium (bone breakdown, kidney reabsorption, vitamin D activation) to show a comprehensive understanding.

 

Question 9. Write on Hyperthyroidism and Hypothyroidism?
Answer:
Hypothyroidism (Underactive Thyroid):
This happens when the thyroid gland produces too little thyroid hormone.

• In Infants (Cretinism): Leads to slow skeletal growth, delayed sexual maturity, reduced mental abilities, thick, wrinkled skin, a large tongue, bloated face, and short limbs. Other symptoms include a low basic metabolic rate (BMR), slow pulse, low body temperature, and high blood cholesterol.
• In Adults (Myxedema or Gull's Disease): Characterized by decreased mental activity, memory loss, slow movements, speech difficulties, and general body weakness. Skin becomes dry and coarse, hair is scarce, the face appears puffy, sexual function is disturbed, BMR is low, appetite is poor, and body temperature is subnormal.

Hyperthyroidism (Overactive Thyroid):
This occurs when the thyroid gland produces too much thyroid hormone.

• Grave's Disease (Thyrotoxicosis or Exophthalmic Goiter): Caused by the hypersecretion of the thyroid. Symptoms include an enlarged thyroid gland, a significantly increased BMR (50%-100%), elevated breathing and excretory rates, increased heart rate, high blood pressure, bulging eyeballs (exophthalmos), and muscle weakness with weight loss.

Both conditions show how important the thyroid gland is for the body's overall health and metabolism.In simple words: Hypothyroidism means your thyroid gland makes too little hormone, causing slow growth and low energy. Hyperthyroidism means it makes too much, leading to fast heart rate, high energy, and bulging eyes.

🎯 Exam Tip: For these contrasting conditions, use clear headings and bullet points for symptoms, separating effects on infants/adults for hypothyroidism, and specifying distinct features like exophthalmos for hyperthyroidism.

 

Question 10. Give an account of the actions of insulin.
Answer: Insulin is a vital hormone produced by the pancreas that plays a key role in managing blood sugar levels. Its main actions include:

• It lowers blood glucose levels by helping body cells, especially muscle and fat cells, absorb glucose from the bloodstream.
• It stops the conversion of amino acids and fats into glucose.
• Insulin is therefore known as a hypoglycemic hormone because it reduces blood sugar.

This hormone ensures that the body uses or stores glucose efficiently, preventing high blood sugar.
In simple words: Insulin helps lower blood sugar by moving glucose into cells and stopping the body from making more sugar from other sources.

🎯 Exam Tip: Focus on insulin's role in glucose uptake by cells and its classification as a hypoglycemic hormone.

 

Question 11. Write on the disorders associated with parathryroid gland?
Answer: The parathyroid gland produces parathormone (PTH), which regulates calcium and phosphate levels in the blood. Problems with this gland can lead to two main disorders:
1. Tetany (Hypoparathyroidism): This is caused by the parathyroid gland secreting too little PTH.

• Blood calcium levels decrease (hypocalcemia), while blood phosphate levels increase.
• This leads to severe muscle cramps, locking of the jaw, and generalized convulsions.
• Heart rate may increase, and body temperature can rise, along with muscular spasms.

2. Hyperparathyroidism: This is caused by the parathyroid gland secreting too much PTH.

• There is an excess of PTH in the blood.
• This leads to demineralization of bones, meaning bones lose calcium and become weak and soft.
• Symptoms include loss of muscle tone, general weakness, and kidney problems (renal disorders) due to excess calcium.

Both conditions highlight the critical role of the parathyroid gland in maintaining mineral balance in the body.
In simple words: Too little parathormone causes tetany, with low blood calcium and muscle cramps. Too much parathormone causes hyperparathyroidism, with high blood calcium and weak bones.

🎯 Exam Tip: When discussing disorders, clearly state whether it's due to *hypo* (too little) or *hyper* (too much) secretion and list distinct symptoms for each.

 

Question 12. a) What are the systems that regulate and co-ordinate the physiological functions of our body? b) Give the meaning of the word “Hormone”. c) What are the general characters of hormone?
Answer:
a) The main systems that control and coordinate the body's functions are:

• The Nervous system (brain, spinal cord, nerves)
• The Endocrine system (glands that produce hormones)

These two systems work together to keep the body running smoothly.
b) The word "Hormone" means "to excite." Hormones are substances that stir up or activate certain processes in the body.
c) General characteristics of hormones:

• The endocrine system uses hormones to influence various metabolic activities in the body.
• Hormones are like chemical messengers. They are released into the bloodstream.
• They travel to specific target organs or tissues where they act, causing a particular effect.

Hormones are powerful chemicals that coordinate many different body functions, from growth to mood.
In simple words: a) The nervous and endocrine systems control our body. b) "Hormone" means "to excite." c) Hormones are chemical messengers from glands that travel in blood to specific places to cause changes.

🎯 Exam Tip: For part (c), ensure you mention that hormones are chemical messengers, travel in blood, and act on target organs. This covers the core definition.

 

Question 13. Write a paragraph on different types of diabetes mellitus?
Answer: Diabetes mellitus, also known as hyperglycemia, is a condition where blood glucose levels are too high due to problems with insulin. There are two main types:
Type I Diabetes (Insulin-dependent diabetes): This type is caused by the body's immune system mistakenly attacking and destroying the cells in the pancreas that produce insulin. As a result, the body produces very little or no insulin. It's often linked to genetic factors, illnesses, or viral infections. People with Type I diabetes need insulin injections to survive.
Type II Diabetes (Non-insulin-dependent diabetes): This type occurs when the body either doesn't produce enough insulin, or the body's cells don't respond well to the insulin it does produce (insulin resistance). It is often associated with lifestyle factors like diet and lack of exercise.
Common symptoms for both types include:

• Polyuria (excessive urination)
• Polyphagia (excessive hunger)
• Polydipsia (excessive thirst)
• Ketosis (breakdown of fat into ketone bodies, especially in Type I, leading to ketone accumulation in blood).

Understanding the differences helps in proper management and treatment of each type.In simple words: Diabetes mellitus means high blood sugar. Type I is when the body can't make insulin. Type II is when the body doesn't use insulin well or makes too little. Both cause frequent urination, hunger, and thirst.

🎯 Exam Tip: Clearly distinguish between Type I (insulin deficiency, autoimmune) and Type II (insulin resistance, lifestyle factors) diabetes, then list the common "poly-" symptoms.

 

Question 14. Give a diagrammatic sketch of the glandular system.
Answer: The diagram should show the major endocrine glands in the human body, including the hypothalamus, pineal gland, pituitary gland, thyroid gland, thymus gland, adrenal glands, pancreas, ovaries (female), and testes (male). The diagram should represent their correct anatomical positions. A clear and well-labeled diagram helps to understand the widespread distribution of the endocrine system.
In simple words: Draw a picture of the human body and label where all the main glands are, like the brain glands, thyroid, pancreas, and reproductive glands.

🎯 Exam Tip: Ensure your diagram includes all major glands and their labels in the correct anatomical positions for full marks.

 

Question 15. Tabulate the major hypothalamic hormones and their functions.
Answer:

The hypothalamus plays a crucial role as the control center for many endocrine functions.
In simple words: The hypothalamus makes many hormones. Each one tells another gland, often the pituitary, to either make or stop making its own hormones.

🎯 Exam Tip: Memorize the releasing and inhibiting hormones from the hypothalamus and which pituitary hormones they affect, as this is a common examination topic.

 

Question 16. Discuss the role of the hypothalamus and pituitary as a coordinated unit in maintaining the physiological process.
Answer: The hypothalamus and pituitary gland work together closely as a team to control many important body processes. They are anatomically different but function as a coordinated unit.

• The hypothalamus is a small, cone-shaped part of the brain that extends downwards to the pituitary stalk.
• It connects the nervous system and the endocrine system, acting as a bridge between them.
• It has special neurosecretory cells that produce neurotransmitters. These chemicals can either act as releasing hormones (telling the pituitary to release its hormones) or as inhibitory hormones (telling it to stop releasing hormones).
• Even though the pituitary gland is often called the "master endocrine gland," it is actually controlled by the hypothalamus.
• The hypothalamus also helps maintain the body's internal balance (homeostasis). This includes regulating blood pressure, body temperature, heart function, and fluid-electrolyte balance. It also influences emotional responses.
• The hypothalamic hypophyseal portal blood vessel system allows the hypothalamus to directly control the anterior pituitary.
• Nerve signals from the hypothalamic hypophyseal axis (a nerve bundle) control the posterior pituitary.
• Together, they make sure various hormones are released at the right time and in the right amounts, ensuring the body's physiological processes run smoothly.

This teamwork is essential because they cannot function correctly as separate parts.
In simple words: The hypothalamus and pituitary gland work like a control center and its main assistant. The hypothalamus, part of the brain, tells the pituitary what hormones to release or stop, controlling many body functions like growth, stress, and metabolism to keep everything balanced.

🎯 Exam Tip: Emphasize the "master-servant" relationship between the hypothalamus (controller) and the pituitary (responder), highlighting their anatomical and functional link for maintaining homeostasis.

 

Question 17. Give the classification of hormones based on their chemical nature?
Answer: Hormones can be classified into different groups based on their chemical structure, which also affects how they work in the body.

This classification helps understand how hormones interact with cell membranes and receptors.
In simple words: Hormones are grouped by what they are made of. Some are amines (like adrenaline), some are proteins (like insulin), and some are steroids (like testosterone).

🎯 Exam Tip: Remember a key feature for each class: Amines are small, Proteins are water-soluble, and Steroids are lipid-soluble (derived from cholesterol) and can easily cross cell membranes.

 

Question 18. Explain the structure of Testis?
Answer: The testes (plural of testis) are the male reproductive glands found inside the scrotal sac. They have two main functions:

• They act as sex organs, producing sperm.
• They also serve as endocrine glands, making male sex hormones.

Each testis is made up of many tiny tubes called seminiferous tubules. Between these tubules are special cells called Leydig cells. These Leydig cells are crucial because they secrete several male sex hormones, which are collectively known as androgens. The most important male sex hormone produced here is testosterone. These hormones are vital for male development and reproductive health.In simple words: Testis are male glands that make sperm and hormones. They contain tiny tubes and Leydig cells which produce male hormones like testosterone.

🎯 Exam Tip: Focus on the dual role of the testis (sex organ and endocrine gland) and mention Leydig cells as the source of androgens, specifically testosterone.

 

Question 19. Give a brief account of the ovary.
Answer: The ovaries are the female reproductive glands, typically found as a pair in the pelvic region of the abdomen. They perform several important roles:

• They are made up of ovarian follicles and stromal tissue.
• Their primary role is to produce eggs (ova).
• They also act as endocrine glands, secreting steroid hormones such as oestrogen and progesterone.

These hormones have several key functions in females:

• Oestrogen: It helps with the maturation of reproductive organs and the development of secondary sexual characteristics during puberty. Along with progesterone, it promotes breast development and starts the menstrual cycle.
• Progesterone: It prepares the uterus for a fertilized egg to implant. It also reduces uterine contractions during pregnancy and helps stimulate the development of mammary glands for milk secretion. Progesterone is also important for the premenstrual changes in the uterus and the formation of the placenta.

The ovaries are vital for both reproduction and the regulation of the female body.
In simple words: Ovaries are female glands that make eggs and hormones like oestrogen and progesterone. These hormones help with puberty, periods, pregnancy, and breast development.

🎯 Exam Tip: When describing the ovary, ensure you mention its dual function (egg production and hormone secretion) and briefly outline the roles of both oestrogen and progesterone.

 

Question 20. Explain the functions of hormones of the heart and kidney.
Answer:
Heart Hormones:
The heart, specifically specialized cells in its atrial walls (cardiocytes), acts as a partial endocrine gland. It secretes an important peptide hormone called Atrial Natriuretic Factor (ANF).

• When blood pressure increases, ANF is released.
• ANF then causes blood vessels to widen (dilate), which helps to reduce high blood pressure.

This hormone helps the body regulate blood volume and pressure.
Kidney Hormones:
The kidneys also function as partial endocrine glands, secreting three key hormones: renin, erythropoietin, and calcitriol.
Renin:

• Secreted by Juxta Glomerular Cells (JGA) in the kidney.
• It increases blood pressure by helping form angiotensin in the blood.

Erythropoietin:

• Also secreted by JGA cells.
• It stimulates erythropoiesis, which is the formation of red blood cells (RBCs) in the bone marrow.

Calcitriol:

• Secreted by the proximal tubules of the nephron (kidney's filtering units).
• It is an active form of vitamin D3.
• It helps the body absorb calcium and phosphorus from the intestines and also speeds up bone formation.

These hormones show how organs beyond the typical endocrine glands play a role in regulating body functions.
In simple words: The heart makes ANF to lower high blood pressure. Kidneys make renin to raise blood pressure, erythropoietin to make red blood cells, and calcitriol to help absorb calcium for bones.

🎯 Exam Tip: For the heart, remember ANF's role in lowering blood pressure. For the kidney, list all three hormones (renin, erythropoietin, calcitriol) and their primary functions.

 

Question 21. If you happen to see a man/lady with short stature how will you identify him? Differentiate and give a reason for that disorder.
Answer: If I see a person with short stature, it could be due to either cretinism or dwarfism. I would look for additional symptoms to differentiate between the two disorders.
Cretinism: This disorder is caused by the *hypo-secretion* (too little) of thyroxine (thyroid hormone) during development. The symptoms include:

• Severely retarded skeletal growth and mental ability.
• Absence of sexual maturity.
• Thick, wrinkled skin, a bloated face, and a protruding enlarged tongue.
• Thick and short limbs.
• Low BMR (Basal Metabolic Rate), slow pulse rate, subnormal body temperature, and elevated blood cholesterol levels.

Dwarfism: This disorder is typically caused by *hypo-secretion* (too little) of growth hormone (GH) during childhood. The symptoms are mainly:

• Skeletal growth is severely arrested, but mental ability is usually normal.
• Sexual maturity is also arrested, meaning they do not develop sexually.
• They typically attain a maximum height of about 4 feet only.

The key difference is that cretinism involves both physical and mental retardation due to thyroid hormone deficiency, whereas dwarfism primarily affects physical growth due to growth hormone deficiency, often with normal mental function. A detailed medical history and blood tests would confirm the diagnosis.
In simple words: A short person could have cretinism (from low thyroid hormone, affecting both body and mind) or dwarfism (from low growth hormone, mostly affecting body height but not usually mind). I would look at other body and mind signs to tell the difference.

🎯 Exam Tip: To differentiate, remember that cretinism involves both physical and mental developmental issues due to thyroxine deficiency, while dwarfism is primarily stunted physical growth due to growth hormone deficiency, often with normal intellect.

 

Question 22. (i) Describe the structure of the pancreas. (ii) Draw the diagram and marced it parts (iii) How insulin controls blood sugar? (iv) What is the role of glucagon in our body?
Answer:
(i) Structure of Pancreas:
The pancreas is a unique gland because it acts as both an exocrine gland (releasing digestive enzymes) and an endocrine gland (releasing hormones). It is shaped like a leaf and is located just below the stomach.
The pancreas is mainly composed of two types of tissues:

• Acme (Acinar cells): These cells make and secrete digestive enzymes that help break down carbohydrates, proteins, and fats in food.
• Islets of Langerhans: These are small clusters of endocrine cells scattered throughout the pancreas. They are responsible for producing hormones. A human pancreas contains about 1-2 million islets.

The Islets of Langerhans contain different types of cells:

• Alpha cells: Make glucagon.
• Beta cells: Make insulin.
• Delta cells: Make somatostatin.

This complex structure allows the pancreas to play a dual role in digestion and blood sugar regulation.
(ii) The diagram should show the pancreas with its exocrine parts (acinar cells, ducts) and its endocrine parts (Islets of Langerhans, with alpha, beta, and delta cells labeled). It should also show its position relative to the stomach and duodenum.
(Please refer to a biology textbook or online resource for a detailed diagram of the pancreas and its cellular structure.)
(iii) How Insulin Controls Blood Sugar:
Insulin is a peptide hormone that plays a crucial role in maintaining blood glucose homeostasis (balance). Its main effects are to lower blood glucose levels by:

• Increasing the uptake of glucose into body cells, especially muscle and fat cells.
• Inhibiting the breakdown of glycogen into glucose.
• Preventing the conversion of amino acids or fats into glucose.

So, insulin is rightly called a hypoglycemic hormone because it reduces blood sugar. When insulin secretion is reduced, glucose levels rise in the blood, leading to diabetes mellitus. There are two types: Type I (lack of insulin production) and Type II (reduced insulin sensitivity or insufficient production).
(iv) Role of Glucagon in our Body:
Glucagon is also a polypeptide hormone, and it has the opposite effect of insulin—it is a potent hyperglycemic hormone. Its primary roles include:

• Acting on the liver to promote the breakdown of stored glycogen into glucose (glycogenolysis), which releases glucose into the blood.
• Promoting the synthesis of glucose from non-carbohydrate sources like lactic acid (gluconeogenesis).

By doing these actions, glucagon increases blood glucose levels. If glucagon activity is too high or insulin is too low, it can lead to prolonged hyperglycemia and diabetes mellitus. Both insulin and glucagon work together to keep blood sugar within a healthy range.
In simple words: (i) The pancreas is a leaf-shaped gland below the stomach that makes digestive juices and hormones like insulin and glucagon from special cell clusters called Islets of Langerhans. (iii) Insulin lowers blood sugar by helping cells take in glucose and stopping the body from making more sugar. (iv) Glucagon raises blood sugar by making the liver release stored sugar and create new sugar.

🎯 Exam Tip: For the pancreas, clearly differentiate its exocrine (digestive enzymes from acinar cells) and endocrine (hormones from Islets of Langerhans) functions. Remember the specific cell types within the islets (alpha, beta, delta) and their respective hormones, as well as the opposing actions of insulin and glucagon on blood glucose.

 

Question 22. (i) Describe the structure of the pancreas.
(ii) Draw the diagram and marced it parts
(iii) How insulin controls blood sugar?
(iv) What is the role of glucagon in our body?
Answer:
i) Structure of pancreas:
The pancreas is a combined gland that performs both endocrine and exocrine functions. It is found just below the stomach and looks like a leaf. The pancreas is made up of two main types of tissues: acinar cells and islets of Langerhans. The acinar cells secrete digestive enzymes, while the islets of Langerhans secrete hormones like insulin and glucagon. A human pancreas has 1-2 million islets of Langerhans. Inside each islet, about 60% are beta cells, 25% are alpha cells, and 10% are delta cells. Alpha cells produce glucagon, beta cells produce insulin, and delta cells produce somatostatin. Pancreatic enzymes are essential for digestion of food.
ii) Structure of Islets of Langerhans (pancreas):
[Diagram of Islets of Langerhans (pancreas) showing exocrine pancreas (acinar cells and duct cells), Alpha cell (secretes glucagon), Delta cell (secretes somatostatin), Red blood cell, F cell (secretes pancreatic polypeptide), Capillaries, Beta cell (secretes insulin), Accessory pancreatic duct, Main pancreatic duct, Major duodenal papilla, Pancreas, Duodenum – will be rendered as an image.]
iii) Insulin control-blood sugar:
Insulin is a peptide hormone that plays a crucial role in maintaining glucose balance in the body. Its main function is to lower blood glucose levels by helping body cells, especially muscle and fat cells, take up more glucose. Insulin also prevents the breakdown of glycogen into glucose and stops the conversion of amino acids or fats into glucose. Because of these actions, insulin is correctly called a hypoglycemic hormone.
iv) Role of Glucagon:
Glucagon is a polypeptide hormone that works against insulin. It is a powerful hyperglycemic hormone, meaning it increases blood glucose levels. Glucagon acts on the liver to promote the breakdown of glycogen into glucose (glycogenolysis). It also helps in making new glucose from lactic acid and non-carbohydrate molecules (gluconeogenesis). This process leads to the release of glucose from liver cells, which raises blood glucose levels. Since glucagon reduces how cells absorb and use glucose, it is called a hyperglycemic hormone. If hyperglycemia continues for a long time, it can lead to diabetes mellitus.
In simple words: The pancreas has parts that make digestive juices and parts that make hormones like insulin and glucagon. Insulin helps lower blood sugar by letting cells absorb it, and glucagon helps raise blood sugar by releasing stored glucose from the liver.

🎯 Exam Tip: Remember that insulin lowers blood sugar (hypoglycemic) while glucagon raises it (hyperglycemic), and they work together to keep blood sugar balanced.

 

Question 23. Symptoms of diabetes
Answer:
The symptoms of diabetes mellitus include:

• Polyuria – This means excessive urination.
• Polyphagia – This refers to excessive intake of food.
• Polydipsia – This is an excessive consumption of liquids due to constant thirst.
• Ketosis – This occurs when fat breaks down into glucose, leading to a build-up of ketone bodies in the blood.
• Gluconeogenesis – This is when the body converts non-carbohydrate forms like amino acids and fat into glucose.

In simple words: Diabetes causes a person to pee, eat, and drink a lot, and also burn fat for energy, which creates ketone bodies.

🎯 Exam Tip: When listing symptoms for a disease, provide specific medical terms like polyuria, polyphagia, and polydipsia for accuracy.

 

Question 24. a) Write down the location and dimension of the pituitary gland?
b) Explain the internal structure of the pituitary gland?
c) Draw the diagram of the pituitary gland and label the parts.
Answer:
a. Location of pituitary gland:

• The pituitary gland is located in a bony space called the sella turcica, which is a depression in the sphenoid bone at the base of the brain. It is also connected to the hypothalamus cerebri.
• It is connected to the brain by a stalk called the infundibulum.
• Its approximate dimensions are about 1 centimeter in diameter and 0.5 grams in weight. This small size shows how important it is for the body.

b. Internal structure:

• The pituitary gland consists of two main lobes: the anterior glandular adenohypophysis and the posterior neural neurohypophysis.
• Anatomically, the anterior lobe (adenohypophysis) has three zones: pars intermedia, pars distalis, and pars tuberalis.
• The neurohypophysis is also known as pars nervosa.
• Embryonic origin: The anterior lobe develops from an embryonic pocket of the pharyngeal epithelium called Rathke's pouch.
• The posterior lobe develops from the base of the brain as an outgrowth of the hypothalamus.

c. Hypothalamus and pituitary gland
[Diagram of the hypothalamus and pituitary gland, showing superior hypophyseal artery, optic chiasma, capillary beds, anterior lobe of pituitary gland, endocrine cells, hypophyseal vein, paraventricular nuclei, supraoptic nuclei, median eminence, infundibulum, interior hypophyseal artery, posterior lobe of pituitary gland, mamillary body – will be rendered as an image.]
In simple words: The pituitary gland is a small gland at the base of the brain, connected by a stalk. It has two main parts, an front part and a back part, each with different origins and structures that control many body functions.

🎯 Exam Tip: When describing glands, always mention their location, size, and how they connect to other parts of the brain or body.

 

Question 25. Give a brief account of the hormones of the adenohypophysis.
Answer:
The adenohypophysis, or anterior pituitary, secretes six main hormones, each playing a vital role in the body:
1. Growth Hormone (GH) or Somatotropic Hormone (STH) or Somatotropin:

• This is a peptide hormone.
• It promotes the growth of all tissues and regulates metabolic processes throughout the body.
• GH affects the metabolism of carbohydrates, proteins, and lipids, increasing the rate at which cells make proteins. This hormone ensures proper development.
• It stimulates the formation of cartilage (chondrogenesis) and bone (osteogenesis).
• It helps the body retain important minerals like nitrogen, potassium, phosphorus, and sodium.

2. Thyroid Stimulating Hormone (TSH) or Thyrotropin:

• TSH is a glycoprotein hormone.
• It stimulates the thyroid gland to release tri-iodothyronine (T3) and thyroxine (T4).
• TSH secretion is regulated by a negative feedback mechanism.
• Its release from the anterior pituitary is triggered by thyrotropin-releasing hormone (TRH) from the hypothalamus.
• When thyroxine levels in the blood rise, TRH acts on both the pituitary and hypothalamus to stop TSH secretion, maintaining balance.

3. Adreno Corticotropic Hormone (ACTH):

• ACTH is a peptide hormone.
• It stimulates the adrenal cortex to secrete glucocorticoids and mineralocorticoids.
• It stimulates melanin synthesis in melanocytes, which in turn causes the release of fatty acids from fat tissues and stimulates insulin secretion.
• Its secretion is also controlled by a negative feedback mechanism.

4. Follicle Stimulating Hormone (FSH):

• FSH is a glycoprotein hormone.
• It regulates the functions of the gonads (testes in males, ovaries in females).
• In males, FSH works with androgens on the germinal epithelium of seminiferous tubules to stimulate sperm production and release (spermatogenesis).
• In females, it acts on the ovaries to help develop and mature Graafian follicles.

5. Luteinizing Hormone (LH):

• LH is a glycoprotein hormone.
• It is also known as interstitial cell-stimulating hormone (ICSH) in males.
• In males, ICSH acts on the interstitial cells of the testes to produce the male sex hormone testosterone.
• In females, LH independently triggers ovulation, helps maintain the corpus luteum, and promotes the creation and release of ovarian hormones.
• FSH and LH secretion typically begins during the pre-pubertal period.
• FSH and LH are collectively known as gonadotropins.

6. Luteotropic Hormone (LTH) or Prolactin:

• LTH is a protein hormone.
• It is also called luteotropin, lactogenic hormone, or mammotropin.
• It stimulates milk secretion after childbirth.
• Because it promotes the development of the corpus luteum, it is named luteotropic hormone. This ensures the ongoing production of important hormones for pregnancy.

In simple words: The front part of the pituitary gland makes many hormones like growth hormone, thyroid stimulating hormone, and hormones for reproduction and milk production, each with different jobs to keep the body working well.

🎯 Exam Tip: When discussing pituitary hormones, remember to differentiate between their functions in males and females, as some have distinct roles.

 

Question 26. a) Name the hormones secreted by the neuro hypophysis?
b) Give a brief account of its functions?
Answer:
a. Neurohypophysis secretes two hormones:
1. Vasopressin or Anti-diuretic hormone (ADH)
2. Oxytocin
b. Vasopressin or Anti-diuretic Hormone (ADH):

• It is a peptide hormone.
• ADH promotes the reabsorption of water and electrolytes by the distal tubules of the nephron, which helps reduce water loss through urine. This makes it crucial for maintaining the body's fluid balance.
• Therefore, it is also known as an anti-diuretic hormone.
• When released in large amounts, it can cause blood vessels to constrict and increase blood pressure.
• A deficiency of ADH causes diabetes insipidus, which leads to the production of a large amount of urine.

Oxytocin:

• Oxytocin literally means "quick birth."
• It is a peptide hormone.
• It stimulates strong contractions of the smooth muscles of the uterus during childbirth, helping in the delivery of the baby.
• It also stimulates the ejection of milk from the mammary glands after birth.

b. Chemical nature of Insulin:

• The insulin hormone is a peptide hormone made of 51 amino acids.
• The molecular weight of insulin is 5734 Daltons.
• It has two chains, A and B, which are linked by disulfide bridges formed between cystine residues.

Role of Insulin:

• Insulin increases the uptake of glucose by body cells, especially muscle and fat cells.
• It stops the breakdown of glycogen into glucose and prevents the conversion of amino acids or fats into glucose.
• Therefore, insulin lowers the blood glucose level and is correctly called a hypoglycemic hormone.

In simple words: The neurohypophysis releases ADH, which helps control water in the body, and oxytocin, which helps with childbirth and milk release. Insulin, a separate hormone, works to lower blood sugar.

🎯 Exam Tip: Remember the specific roles of ADH (water balance) and oxytocin (reproduction) from the neurohypophysis, and distinguish them from insulin's role in glucose regulation.

 

Question 27. a) Why hormones are called chemical messengers?
b) Explain how the target organs are specifically fit for the action of hormones?
Answer:
a) Why hormones are called chemical messengers:
Hormones are called chemical messengers because they act as organic catalysts and co-enzymes, carrying specific signals from endocrine glands through the bloodstream to target organs. They help coordinate various bodily functions. These messengers travel long distances to trigger specific actions.
b) How target organs are specifically fit for the action of hormones:

• Target organs contain special receptor molecules either on their surface or inside their cells. These receptors are like locks that only a specific hormone (the key) can fit.
• Even though different hormones circulate in the blood, only the cells with the correct receptor molecules for a particular hormone will be activated. Other hormones that come into contact with cells lacking their specific receptors cannot activate them. This ensures that hormones act precisely where needed.
• A single hormone can have multiple effects on the same target tissue or different effects on different target tissues, depending on the receptor type.
• Many hormones cause long-term changes, such as growth, puberty, and pregnancy.
• Serious lack or excess of hormones leads to disorders.
• Hormones work together to coordinate different physical and mental activities, helping to maintain homeostasis (a stable internal body environment).

In simple words: Hormones are like special mail carriers that deliver messages to specific cells, called target organs, using unique receptors. This ensures each hormone does its particular job and helps keep the body balanced.

🎯 Exam Tip: Emphasize the lock-and-key model for hormone action, where specific receptors on target cells ensure precise hormonal responses.

 

Question 28. Draw the Endocrine gland is our body.
Answer:
[Diagram showing the location of various endocrine glands in the human body, including the hypothalamus, pineal gland, pituitary gland, thyroid gland, thymus gland, adrenal glands, pancreas, ovary (female), and testis (male) – will be rendered as an image.]
In simple words: This image shows where all the main glands in our body are located, which produce hormones to control different functions.

🎯 Exam Tip: For diagrams of the human body, correctly labeling all parts is as important as the drawing itself. Practice drawing and labeling each gland's exact position.

 

Question 29. Give an account on parathyroid hormones its hypo and hyper secretion deficiencies.
Answer:
The parathyroid glands are four tiny glands located on the posterior wall of the thyroid glands in humans. They are made of two types of cells: chief cells and oxyphil cells. The chief cells are responsible for secreting parathyroid hormone (PTH). The exact function of oxyphil cells is not yet known. PTH is vital for calcium and phosphate balance in the body. It plays a critical role in regulating bone health and mineral absorption.
Functions of Parathyroid Hormone (PTH):

• PTH helps control calcium and phosphate levels in the blood.
• It promotes the activation of vitamin D, which in turn increases calcium absorption by the intestine.
• PTH increases blood calcium levels by stimulating osteoclasts to dissolve bone matrix, releasing calcium and phosphate into the blood.
• It also enhances the reabsorption of calcium and the excretion of phosphates by the renal tubules.

Hypersecretion of PTH (Hyperparathyroidism):

• Excessive PTH leads to hyperparathyroidism, causing demineralization of bones, meaning bones lose their calcium.
• This results in increased calcium and phosphate levels in the blood.
• Symptoms include softening of bones, loss of muscle tone, general weakness, and renal disorders due to kidney stone formation.

Hyposecretion of PTH (Hypoparathyroidism):

• A deficiency in PTH causes hypoparathyroidism, leading to a decrease in serum calcium levels (hypocalcemia) and an increase in serum phosphate levels.
• This can result in generalized convulsions, jaw locking, increased heartbeat, higher body temperature, and muscular spasms, a condition known as tetany.

In simple words: Parathyroid glands make PTH, which controls calcium and phosphate. Too much PTH makes bones weak and increases blood calcium, while too little causes muscle problems and low blood calcium.

🎯 Exam Tip: When discussing hormonal disorders, always clearly link the hormone's normal function to the symptoms caused by both its under-secretion (hypo) and over-secretion (hyper).

 

Question 30. a. Give an account of position of adrenal gland and it's internal structure, b. List out the function of adrenal hormone.
Answer:
a) Position and Structure of Adrenal Gland:
A pair of adrenal glands are located at the anterior (top) end of each kidney, which is why they are also known as suprarenal glands. Each adrenal gland is composed of an outer cortex and an inner medulla. The cortex itself has three layers:
1. Zona glomerulosa: This is the outermost layer and makes up about 15% of the cortex. It secretes mineralocorticoids, which are involved in regulating water and electrolyte balance.
2. Zona fasciculata: This is the middle and widest layer, forming about 75% of the cortex. It secretes glucocorticoids, such as cortisol and corticosterone, and small amounts of adrenal androgens and estrogens. Glucocorticoids are important for metabolism and stress response.
3. Zona reticularis: This is the innermost layer of the adrenal cortex, making up about 10% of the cortex. It secretes adrenal androgens and small amounts of estrogen and glucocorticoids.
b) Functions of Adrenal Hormones:

• Glucocorticoids: These hormones, primarily cortisol, stimulate gluconeogenesis (the production of glucose from non-carbohydrate sources). They are also involved in maintaining cardiovascular and kidney functions. Cortisol produces anti-inflammatory effects, suppresses the immune response, and stimulates red blood cell (RBC) production. Because of its crucial role in stress response, it is often called a stress combat hormone.
• Mineralocorticoids: These hormones, mainly aldosterone, regulate the body's water and electrolyte balance. They help retain minerals like sodium in the body.
• Androgens: Adrenal androgens play a role in hair growth in the pubic and axial (armpit) regions during puberty.

In simple words: Adrenal glands sit on top of the kidneys and have an outer part (cortex) and an inner part (medulla). The cortex makes hormones like cortisol for stress, aldosterone for water balance, and some sex hormones, which help the body handle various situations.

🎯 Exam Tip: Remember the three distinct layers of the adrenal cortex and the specific types of hormones (glucocorticoids, mineralocorticoids, androgens) each layer produces, along with their primary functions.