ICSE Class 10 Biology Board Exam Question Paper 2011 with Solutions

ICSE Class 10 Biology Board Exam Question Paper with Solutions

SECTION-I (40 Marks)
(Attempt all questions from this Section.)

Question 1

(a) Name the following: [5 Marks]
(i) The mineral element essential for the clotting of blood.
(ii) The cells of the testes that produce male hormones.
(iii) The nutritive layer of the eye which also prevents reflection of light.
(iv) The structural and functional unit of the kidney.
(v) That part of the chloroplast where the light reaction of photosynthesis takes place.

Answer:
(i) Calcium
(ii) Interstitial cells (Leydig cells)
(iii) Choroid
(iv) Nephron
(v) Grana (or Thylakoids)

Teacher's Note:
a) This question tests fundamental biological terminology and knowledge of basic structures and their functions in the human body and plants.
b) Students should be precise with scientific terms; for instance, "Interstitial cells" is more accurate than just "Leydig cells" if the latter is not explicitly taught, and "Grana" or "Thylakoids" are acceptable for the site of light reaction.

(b) State the main function of the following : [5 Marks]
(i) Yellow spot.
(ii) Coronary artery
(iii) Medulla oblongata
(iv) Thrombocytes
(v) Vitreous humour

Answer:
(i) Yellow spot: It is the area of best vision on the retina, having the maximum number of cone cells, and perceives the image in the best and most detailed manner.
(ii) Coronary artery: It supplies oxygenated blood to the walls of the heart muscle (myocardium) itself.
(iii) Medulla oblongata: It controls all involuntary activities of the body such as heartbeat, breathing, blood pressure, swallowing, coughing, sneezing, and vomiting.
(iv) Thrombocytes (Platelets): They help in blood clotting by producing thromboplastin (platelet factor 3) at the site of injury.
(v) Vitreous humour: It is a jelly-like substance that fills the posterior chamber of the eye, giving the eyeball its spherical shape and maintaining pressure.

Teacher's Note:
a) When stating functions, ensure to provide a clear and concise explanation that highlights the primary role of the structure or component.
b) For terms like "Thrombocytes," knowing the alternative name (platelets) can be helpful, and specifying the key substance (thromboplastin) involved in their function is important for full marks.

(c) Copy and complete the following by filling in the blanks 1 to 5 with appropriate words/terms/phrases: [5 Marks]
To test the leaf for starch, the leaf is boiled in water to .......... (1). It is next boiled in methylated spirit to .......... (2). The leaf is placed in warm water to soften it. It is then placed in a dish and .......... (3) solution is added. The region, which contains starch, turns .......... (4) and the region, which does not contain starch, turns .......... (5).

Answer:
To test the leaf for starch, the leaf is boiled in water to (1) kill the cells. It is next boiled in methylated spirit to (2) remove chlorophyll. The leaf is placed in warm water to soften it. It is then placed in a dish and (3) iodine solution is added. The region, which contains starch, turns (4) blue black and the region, which does not contain starch, turns (5) brown.

Teacher's Note:
a) This question describes the standard procedure for testing a leaf for starch, a common experiment in biology. Each step has a specific purpose that students should understand.
b) Key terms to remember are the reagents used (methylated spirit, iodine solution) and the characteristic colour changes (blue-black for starch, brown/yellow for no starch).

(d) Give the exact location of: [5 Marks]
(i) Hydathodes
(ii) Organ of corti
(iii) Mitral valve
(iv) Pituitary gland
(v) Amnion.

Answer:
(i) Hydathodes: On the margins/tips of leaves of some plants, especially herbaceous plants.
(ii) Organ of corti: In the endolymph present in the middle canal (scala media or cochlear duct) of the cochlea in the inner ear.
(iii) Mitral valve (Bicuspid valve): Between the left auricle (atrium) and the left ventricle of the heart.
(iv) Pituitary gland: At the base of the midbrain, attached to the hypothalamus by a stalk (infundibulum), within the sella turcica of the sphenoid bone.
(v) Amnion: Around the embryo in the uterus, forming the amniotic sac.

Teacher's Note:
a) For location-based questions, precision is key. Mentioning the specific organ, tissue, or anatomical landmark is crucial.
b) Students should differentiate between general locations and exact anatomical positions, for example, not just "in the ear" but "in the cochlea, in the endolymph of the middle canal."

(e) State whether the following statements are true or false. If false rewrite the correct form of the statement by changing the first or last word only. [5 Marks]
(i) Lysosomes is a part of the cell in which chromosomes are present.
(ii) Urethra carries urine from kidney to the urinary bladder.
(iii) Centromere is the organelle of the cell that initiates cell division.
(iv) Gestation is the process of fixing of the zygote to the uterine wall.
(v) Pencillin obtained from Pencillium notatum is an antibody.

Answer:
(i) False; Nucleus is a part of the cell in which chromosomes are present.
(ii) False; Ureter carries urine from kidney to the urinary bladder.
(iii) False; Centrosome is the organelle of the cell that initiates cell division.
(iv) False; Implantation is the process of fixing of the zygote to the uterine wall.
(v) False; Penicillin obtained from Penicillium notatum is an antibiotic.

Teacher's Note:
a) This question requires careful reading and accurate biological knowledge to identify false statements and correct them by changing only the specified word (first or last).
b) Common errors include changing more than one word or providing a correct statement that doesn't adhere to the "first or last word only" rule. For example, for (i), changing "Lysosomes" to "Nucleus" is correct, and for (v), changing "antibody" to "antibiotic" is correct.

(f) Rewrite the complete the following sentences by inserting the correct word in the space indicated : [5 Marks]
(i) .......... vaccine is given to build up immunity against polio.
(ii) Phenotype is the observable characteristic which is ......... controlled.
(iii) Wooden doors swell up in rainy season due to ..........
(iv) The blood vessel that begins and ends in capillaries is the ..........
(v) .......... is the phenomenon of contraction of the cytoplasm from the cell wall.

Answer:
(i) Salk's vaccine is given to build up immunity against polio.
(ii) Phenotype is the observable characteristic which is genetically controlled.
(iii) Wooden doors swell up in rainy season due to imbibition.
(iv) The blood vessel that begins and ends in capillaries is the hepatic portal system.
(v) Plasmolysis is the phenomenon of contraction of the cytoplasm from the cell wall.

Teacher's Note:
a) This fill-in-the-blanks section tests specific biological terms and concepts across various chapters.
b) Students should ensure they use the most appropriate and precise term for each blank, such as "Salk's" for the polio vaccine or "hepatic portal system" for the specific blood vessel described.

(g) Study the following diagram carefully and then answer the questions that follow : [5 Marks]

[Figure: Diagram showing three cells labelled A, B, C. Cell 1 is a biconcave disc (Red Blood Cell). Cell 2 is an amoeboid cell with a nucleus (White Blood Cell). Process A shows cell 2 squeezing through a capillary wall. Process B shows cell 2 engulfing a bacterium. Process C shows cell 2 completely engulfing the bacterium.]

(i) Name the cell labelled 1.
(ii) Identify the phenomenon occurring in A.
(iii) Mention two structural differences between 1 and 2.
(iv) Name the process occurring in B and C and state the importance of this process in the human body.

Answer:
(i) Red blood cell (Erythrocyte)
(ii) Diapedesis
(iii)

(iv) Phagocytosis. This process is important in the human body as it allows white blood cells (specifically phagocytes like neutrophils and macrophages) to engulf and destroy disease-causing germs, foreign particles, and cellular debris, thus defending the body against infections and maintaining tissue health.

Teacher's Note:
a) This question tests the understanding of blood cell types and their functions, particularly the defensive roles of white blood cells.
b) For differences, presenting them in a tabular format is clear and concise. For the process in B and C, naming it and explaining its importance in immunity is essential.

(h) Match the items in Column I with that which is most appropriate in Column II. [5 Marks]

Answer:

Teacher's Note:
a) Matching questions require precise knowledge of terms and their corresponding definitions or functions. Students should carefully evaluate all options before making a match.
b) For (2) Stroma, it is the site of the dark reaction (Calvin cycle) in photosynthesis, while grana (thylakoids) are the site of the light reaction. The official key incorrectly maps Stroma to (c) Site of light reaction; the correct match is (g) Site of dark reaction. For (4) Prolactin, while it is secreted by the anterior pituitary (i), its most appropriate function listed is (f) stimulating milk production.

SECTION-II (40 Marks)
(Attempt any Four questions from this Section.)

Question 2

(a) Study the diagram given below and then answer the questions that follow : [5 Marks]

[Figure: Diagram of a nephron. Label 1 points to the afferent arteriole, 2 to the glomerulus, 3 to Bowman's capsule, and 4 to the efferent arteriole.]

(i) Name the region in the kidney where the above structure is present?
(ii) Name the parts labelled 1, 2, 3 and 4.
(iii) Name the stages involved in the formation of urine.
(iv) What is the technical term given to the process occurring in 2 and 3? Briefly describe the process.

Answer:
(i) Cortex
(ii) 1 - Afferent arteriole
2 - Glomerulus
3 - Bowman's capsule
4 - Efferent arteriole
(iii) The stages involved in the formation of urine are:
1. Ultrafiltration (or Glomerular filtration)
2. Selective reabsorption
3. Tubular secretion
(iv) The technical term for the process occurring in 2 (Glomerulus) and 3 (Bowman's capsule) is Ultrafiltration (or Glomerular filtration).
Description of the process: Blood rich in nitrogenous waste and excess water enters the Bowman's Capsule through a wider afferent arteriole. This arteriole then splits into a fine network of capillaries called the glomerulus. Due to the difference in diameter between the afferent and efferent arterioles, a high hydrostatic pressure is created within the glomerulus. This pressure forces water, salts, glucose, amino acids, urea, and other small solutes from the blood plasma through the semi-permeable walls of the glomerulus and Bowman's capsule into the capsular space, forming the glomerular filtrate. Blood cells and large protein molecules are retained in the blood due to their size.

Teacher's Note:
a) Understanding the structure of the nephron and the process of urine formation is fundamental. Students should be able to identify all parts and explain their roles.
b) When describing ultrafiltration, it's crucial to mention the role of hydrostatic pressure and the selective permeability of the glomerular capillaries and Bowman's capsule, which allows small molecules to pass while retaining larger ones.

(b) Give reasons for the following: [5 Marks]
(i) Photosynthesis is considered as a process supporting all life on earth.
(ii) A matured mammalian erythrocyte lacks nucleus and mitochondria.
(iii) Potato cubes when placed in water become firm and increase in size.
(iv) Urine is slightly thicker in summer than in winter.
(v) People living in hilly regions usually suffer from simple goitre.

Answer:
(i) Photosynthesis is considered a process supporting all life on earth because it is the primary process by which green plants convert light energy into chemical energy, producing food (glucose) that forms the base of almost all food chains. Additionally, it releases oxygen into the atmosphere, which is essential for the respiration of most living organisms.
(ii) A matured mammalian erythrocyte (red blood cell) lacks a nucleus to provide more space for haemoglobin, thus increasing its oxygen-carrying capacity. It lacks mitochondria to ensure that the oxygen it transports is not consumed by its own metabolic processes, allowing maximum oxygen delivery to tissues.
(iii) Potato cubes when placed in water become firm and increase in size because water is a hypotonic medium compared to the cell sap inside the potato cells. This causes water to move into the potato cells by endosmosis, making the cells turgid and the cubes firm and larger.
(iv) Urine is slightly thicker in summer than in winter because in summer, the body loses a large amount of water through perspiration (sweating) and direct evaporation. To maintain the body's osmotic concentration, the kidneys reabsorb more water from the renal tubules of the nephron, resulting in less water being excreted and thus thicker, more concentrated urine. In winter, less water is lost through sweat, leading to less reabsorption and thinner urine.
(v) People living in hilly regions usually suffer from simple goitre because the soil and water in these areas are often deficient in iodine. Iodine is an essential component for the synthesis of thyroid hormones (thyroxine). A deficiency of iodine leads to insufficient thyroid hormone production, causing the thyroid gland to enlarge in an attempt to compensate, resulting in simple goitre.

Teacher's Note:
a) This question tests the ability to provide scientific reasons for biological phenomena. Each reason should be clear, concise, and biologically accurate.
b) For questions involving processes like osmosis or hormonal regulation, ensure to explain the underlying mechanism (e.g., hypotonic medium for endosmosis, iodine for thyroid hormone synthesis).

Question 3

(a) Study the diagram given below and then answer the questions that follow : [5 Marks]

[Figure: A flow diagram showing the interrelationship between Liver, Pancreas, Glucagon, and Insulin. Glucagon points from Pancreas to Liver. Insulin points from Pancreas to Liver. Liver points to both Glucagon and Insulin.]

(i) Name the cells of the pancreas that produce (1) glucagon (2) insulin.
(ii) State the main function of (1) glucagon (2) insulin.
(iii) Why is the pancreas referred to as an exo-endocrine gland ?
(iv) Why is insulin not given orally but is injected into the body?
(v) What is the technical term for the cells of the pancreas that produce endocrine hormones?
(vi) Where in the body is the pancreas located?

Answer:
(i) (1) Glucagon - Produced by alpha cells of the pancreas.
(2) Insulin - Produced by beta cells of the pancreas.
(ii) (1) Glucagon - It helps to convert glycogen to glucose in the liver, thereby increasing blood glucose levels when they fall.
(2) Insulin - It helps to convert excess glucose to glycogen in the liver and muscles, thereby lowering blood glucose levels when they are high.
(iii) The pancreas is referred to as an exo-endocrine gland because it performs both exocrine and endocrine functions. As an exocrine gland, it secretes pancreatic juice containing digestive enzymes (e.g., amylase, lipase, trypsin) into the duodenum through the pancreatic duct. As an endocrine gland, it secretes hormones like insulin, glucagon, and somatostatin directly into the bloodstream.
(iv) Insulin is a protein by composition. If it were given orally, it would be digested by the proteolytic enzymes in the stomach and small intestine, rendering it inactive and unable to perform its function of regulating blood glucose.
(v) The technical term for the cells of the pancreas that produce endocrine hormones is Islets of Langerhans.
(vi) The pancreas is located in the abdomen, posterior to the stomach, in the loop of the small intestine (duodenum).

Teacher's Note:
a) This question covers the dual nature of the pancreas and the roles of its key hormones in glucose regulation. Students should clearly distinguish between exocrine and endocrine functions.
b) Understanding why insulin cannot be taken orally (due to its protein nature and digestion) is a common conceptual point tested in exams.

(b) With reference to the functioning of the eye, answer the questions that follow : [5 Marks]
(i) What is meant by power of accommodation of the eye ?
(ii) What is the shape of the lens during (1) near vision (2) distant vision?
(iii) Name the two structures in the eye responsible for bringing about the change in the shape of the lens.
(iv) Name the cells of the retina and their respective pigments which get. activated (1) in the dark (2) in light.

Answer:
(i) Power of accommodation of the eye is the ability of the eye lens to change its focal length (by altering its curvature/thickness) to focus objects at varying distances clearly on the retina.
(ii) 1. During near vision: The shape of the lens is more convex or rounded.
2. During distant vision: The shape of the lens is less convex or flatter.
(iii) The two structures responsible for bringing about the change in the shape of the lens are the ciliary muscles and the suspensory ligaments.
(iv) 1. In the dark: The cells activated are rods, and their pigment is rhodopsin.
2. In the light: The cells activated are cones, and their pigment is iodopsin (or photopsin/cone pigments).

Teacher's Note:
a) This question focuses on the physiology of vision, particularly accommodation and photoreception. Students should understand the mechanisms involved in focusing and light detection.
b) It's important to remember the specific cells (rods and cones) and their associated pigments (rhodopsin and iodopsin) for vision in different light conditions.

Question 4

(a) The diagram alongside represents circulation in the human body. Answer the questions that follow : [5 Marks]

[Figure: A simplified diagram of human circulation. Lungs are connected to Heart by vessel 1. Heart is connected to Liver by vessel 7, to Small Intestine by an artery, and to Kidney by an artery. Small Intestine is connected to Liver by vessel 3. Liver is connected to Heart by vessel 6. Kidney is connected to Heart by vessels 4 (artery) and 5 (vein). Vessel 2 is an artery leaving the heart to the body.]

(i) Name the blood vessels labelled 1, 3, 6, and 7,
(ii) Name the blood vessel that supplies the walls of the heart with oxygen.
(iii) Draw a neat labelled diagram of the blood vessel numbered '2' as seen in a cross section.
(iv) Mention one structural difference between blood vessels numbered 4 and 5.

Answer:
(i) 1 - Pulmonary vein
3 - Hepatic portal vein
6 - Hepatic vein
7 - Posterior vena cava (or Inferior vena cava)
(ii) Coronary artery
(iii)

[Figure: Diagram to be added. A cross-section of an artery (blood vessel 2) showing three distinct layers: Tunica externa (outermost connective tissue), Tunica media (middle thick muscular and elastic layer), and Tunica interna (innermost endothelial layer), surrounding a narrow lumen.]

(iv)

Teacher's Note:
a) This question assesses knowledge of the human circulatory system, including specific blood vessels and their characteristics. Identifying the vessels based on their connections to organs is crucial.
b) When asked to draw a diagram, a clear, well-labelled sketch is expected. For differences, a tabular format is preferred for clarity and ease of comparison.

(b) With reference to the human ear, answer the questions that follow : [5 Marks]
(i) Give the technical term for the structure found in the inner ear.
(ii) Name the three small bones present in the middle ear. What is the biological term for them collectively?
(iii) Name the part of the ear associated with (1) static balance (2) hearing (3) dynamic balance.
(iv) Name the nerve, which transmits messages from the ear to the brain.

Answer:
(i) The technical term for the structure found in the inner ear is Membranous labyrinth.
(ii) The three small bones present in the middle ear are Malleus (hammer), Incus (anvil), and Stapes (stirrup). Collectively, they are called Ear ossicles.
(iii) (1) Static balance: Utriculus and Sacculus (parts of the vestibule)
(2) Hearing: Cochlea
(3) Dynamic balance: Semicircular canals
(iv) The nerve which transmits messages from the ear to the brain is the Auditory nerve (or Vestibulocochlear nerve).

Teacher's Note:
a) This question tests detailed knowledge of the structure and function of the human ear, including its role in both hearing and balance.
b) Students should be precise with anatomical names (e.g., Malleus, Incus, Stapes) and understand which parts are responsible for specific sensory functions (static balance, dynamic balance, hearing).

Question 5

(a) The diagram below represents two reproductive cells A and B. Study the same and then answer the questions that follow : [5 Marks]

[Figure: Diagram showing two reproductive cells. Cell A is a large, spherical cell with a nucleus (Ovum). Cell B is a smaller cell with a head, middle piece, and tail (Sperm).]

(i) Identify the reproductive cells A and B.
(ii) Name the specific part of the reproductive system where the above cells are produced.
(iii) Where in the female reproductive system to these cells unite ?
(iv) Name the main hormones secreted by the (1) ovary (2) testes.
(v) Name an accessory gland found in the male reproductive system and state the function of its secretion.

Answer:
(i) A - Ovum (Egg cell)
B - Sperm
(ii) Ovum is produced in the germinal layers of the ovary.
Sperm is produced in the seminiferous tubules of the testis.
(iii) These cells unite in the fallopian tube (oviduct) in the female reproductive system.
(iv) (1) Hormones secreted by the ovary: Oestrogen and Progesterone.
(2) Hormone secreted by the testes: Testosterone.
(v) An accessory gland found in the male reproductive system is the Seminal Vesicle. Its secretion (seminal fluid) contains fructose, which provides energy for the motility of sperm.

Teacher's Note:
a) This question covers the basics of human reproduction, including gamete identification, sites of production, fertilization, and hormonal control.
b) For hormones, it's good to list the primary ones. For accessory glands, naming the gland and its specific contribution to semen is important.

(b) The diagram below represents a layer of epidermal cells showing a fully-grown root hair. Study the diagram and answer the questions that follow : [5 Marks]

[Figure: Diagram of a root hair cell. Label A points to the cell wall, B to the cell membrane, C to the cytoplasm, and D to the nucleus.]

(i) Name the parts labelled A, B, C and D.
(ii) The root hair cell is in a turgid state. Name and explain the process that caused this state.
(iii) Mention one distinct difference between the parts labelled A and B.
(iv) Draw a diagram of the above root hair cell as it would appear when concentrated solution of fertilizers is added near it.

Answer:
(i) A - Cell wall of root hair
B - Cell membrane of root hair
C - Cytoplasm
D - Nucleus
(ii) The process that caused the root hair cell to be in a turgid state is Endosmosis. This occurs because the soil water (outside the root hair cell) is a hypotonic solution compared to the cell sap inside the root hair cell. Consequently, water molecules move from the region of higher water potential (soil) to the region of lower water potential (cell sap) across the semi-permeable cell membrane, causing the cell to swell and become turgid.
(iii)

(iv)

[Figure: Diagram to be added. A root hair cell showing plasmolysis. The cell wall remains intact, but the protoplast (cell membrane, cytoplasm, and nucleus) has shrunk and pulled away from the cell wall, with a small vacuole.]

Teacher's Note:
a) This question tests the understanding of plant cell structure, water absorption by roots, and the principles of osmosis and plasmolysis.
b) When explaining endosmosis, clearly state the relative tonicity of the solutions. For drawing, ensure the diagram accurately depicts plasmolysis, showing the protoplast shrinking away from the cell wall.

Question 6

(a) The diagram below represents a stage during cell division. Study the same and then answer the questions that follow : [5 Marks]

[Figure: Diagram of a cell undergoing mitosis. Chromosomes are aligned at the equatorial plate. Label 1 points to a centriole, 2 to a spindle fibre, and 3 to a chromatid.]

(i) Name the parts labelled 1, 2 and 3.
(ii) Identify the above stage and give a reason to support your answer.
(iii) Mention where in the body this type of cell division occurs.
(iv) Name the stage prior to this stage and draw a diagram to represent the same.

Answer:
(i) 1 - Centriole
2 - Spindle fibre
3 - Chromatid
(ii) The above stage is Metaphase.
Reason: In this stage, the chromosomes are clearly visible and are aligned at the equatorial plate (metaphase plate) of the cell, with their centromeres positioned on the plate and spindle fibres attached to the centromeres.
(iii) This type of cell division (mitosis) occurs in the somatic cells (body cells) for growth, repair, and replacement of old cells.
(iv) The stage prior to Metaphase is Prophase.

[Figure: Diagram to be added. A cell in Prophase. Chromatin condenses into visible chromosomes, each with two sister chromatids. The nuclear envelope begins to disappear, and spindle fibres start to form from the centrioles moving to opposite poles. No distinct equatorial plate yet.]

Teacher's Note:
a) This question tests the understanding of the stages of mitosis. Accurate identification of the stage and its characteristic features is crucial.
b) The provided diagram clearly shows chromosomes aligned at the metaphase plate, indicating Metaphase. The official key incorrectly identifies it as Anaphase and then describes Metaphase for the prior stage. Students must correctly identify the stage shown and then describe the preceding stage.

(b) Study the diagram given below and answer the questions that follow : [5 Marks]

[Figure: An experimental setup for demonstrating transpiration. A potted plant is placed inside a bell jar. The bell jar is sealed at the bottom. The plant is placed on a test tube containing water, with a layer of oil on top of the water. The water level in the test tube is indicated.]

(i) Name the process being studied in the above experiment.
(ii) Explain the process mentioned in (i) above.
(iii) Why is oil placed over water?
(iv) What do we observe with regard to the level of water when this set up is placed in (1) bright sunlight (2) humid conditions (3) windy day?
(v) Mention any three adaptations found in plants to overcome the process mentioned in (ii) above.

Answer:
(i) The process being studied is Transpiration.
(ii) Transpiration is the process of loss of water in the form of water vapour from the aerial parts of a plant, primarily through the stomata on leaves, but also through lenticels on stems and the cuticle.
(iii) Oil is placed over water in the test tube to prevent direct evaporation of water from the surface of the water in the test tube, ensuring that any water loss observed is solely due to transpiration from the plant.
(iv) When this setup is placed in:
1. Bright sunlight: The level of water will fall faster (due to increased rate of transpiration).
2. Humid conditions: The level of water will fall very slowly (due to reduced transpiration rate).
3. Windy day: The level of water will fall faster (due to increased rate of transpiration).
(v) Three adaptations found in plants to overcome (reduce) transpiration are:
1. Presence of a thick cuticle on the leaf surface.
2. Leaves are absent or reduced to spines (e.g., in cacti).
3. Stomata are sunken (located in pits) or covered by hair (e.g., in xerophytes).
4. Fewer stomata on the leaf surface.

Teacher's Note:
a) This question tests the understanding of transpiration, factors affecting its rate, and plant adaptations to minimize water loss.
b) When explaining the effect of environmental factors, link them directly to how they influence the rate of water vapour diffusion from the leaf. For adaptations, provide specific structural features.

Question 7

(a) (i) During a street fight between two individuals, mention the effects on the following organs by the autonomous nervous system, in the table given below: (one has been done for you as an example). [5 Marks]

(ii) List four major activities of the Red cross.

Answer:
(i)

(ii) Four major activities of the Red Cross are:
1. Providing medical aid and relief to victims of natural calamities like floods, famines, earthquakes, etc.
2. Providing blood and medical aid to wounded soldiers during war and assisting prisoners of war.
3. Organizing workshops and campaigns to create awareness among people on health, hygiene, and disaster preparedness.
4. Providing training for health workers and midwives, and promoting health education in communities.

Teacher's Note:
a) This question tests the understanding of the antagonistic actions of the sympathetic and parasympathetic nervous systems, especially in a "fight or flight" scenario.
b) For the Red Cross activities, focus on its humanitarian roles in disaster relief, health services, and community education. The key's point "Trans mid wives" was ambiguous; it has been rephrased to reflect a common Red Cross activity related to health training.

(b) Write down the difference between the following pairs as indicated within the brackets: [5 Marks]
(i) Antiseptic and disinfectant (an example for each)
(ii) Erythrocytes and leucocytes (function)
(iii) Guttation and bleeding in plants (cause)
(iv) NADP and AIDS (expand the abbreviation)
(v) Monohybrid and Dihybrid cross (phenotypic ratio).

Answer:
(i) Antiseptic and Disinfectant (example for each):
Antiseptic: Applied to living tissues to reduce the possibility of infection (e.g., Boric acid, Dettol, Savlon).
Disinfectant: Applied to non-living surfaces or objects to destroy microorganisms (e.g., Lysol, Phenol, Bleaching powder).
(ii) Erythrocytes and Leucocytes (function):
Erythrocytes (Red Blood Cells): Their primary function is to transport respiratory gases (oxygen from the lungs to tissues and a small amount of carbon dioxide from tissues to the lungs) with the help of haemoglobin.
Leucocytes (White Blood Cells): Their primary function is to provide immunity and protect the body from disease-causing germs, foreign particles, and infections by phagocytosis or by producing antibodies.
(iii) Guttation and Bleeding in plants (cause):
Guttation: Caused by root pressure when transpiration is low (e.g., in warm, humid conditions at night) and water absorption is high, leading to the exudation of xylem sap from hydathodes.
Bleeding in plants: Caused by injury to the plant stem or other parts, leading to the exudation of sap (xylem sap or phloem sap) due to root pressure or turgor pressure.
(iv) NADP and AIDS (expand the abbreviation):
NADP: Nicotinamide Adenine Dinucleotide Phosphate
AIDS: Acquired Immuno Deficiency Syndrome
(v) Monohybrid and Dihybrid cross (phenotypic ratio):
Monohybrid cross: The phenotypic ratio of the F2 generation is 3:1 (3 Dominant : 1 Recessive).
Dihybrid cross: The phenotypic ratio of the F2 generation is 9:3:3:1 (9 Dominant for both traits : 3 Dominant for first, Recessive for second : 3 Recessive for first, Dominant for second : 1 Recessive for both traits).

Teacher's Note:
a) This question requires students to differentiate between pairs of biological terms based on specific criteria. Clarity and accuracy in defining the differences are essential.
b) For abbreviations, ensure correct spelling of each word. For genetic crosses, remember the specific F2 phenotypic ratios and what each number represents in terms of traits.