Maharashtra Board Class 11 Psychology Chapter 7 Nervous System Solutions

Nervous System Class 11 Psychology Chapter 7 Questions And Answers

Exercise 1A. Complete The Following Statements With Appropriate Options.

Question 1. Brain is a part of _____ nervous system.
(a) central
(b) peripheral
(c) somatic
Answer: (a) central
In simple words: The brain is the primary organ of the central nervous system, responsible for controlling most body functions.

🎯 Exam Tip: Remember the basic classification of the nervous system into central and peripheral to correctly identify brain components.

 

Question 2. _____ are the building blocks of the nervous system.
(a) Cells
(b) Neurons
(c) Tissues
Answer: (b) Neurons
In simple words: Neurons are specialized cells that transmit electrical and chemical signals, forming the fundamental units of the nervous system.

🎯 Exam Tip: Understanding neurons as the functional units is crucial for grasping how the nervous system operates.

 

Question 3. _____ nervous system prepares us for the fight or flight responses.
(a) Somatic
(b) Parasympathetic
(c) Sympathetic
Answer: (c) Sympathetic
In simple words: The sympathetic nervous system is responsible for activating the body's 'fight or flight' response in stressful or dangerous situations.

🎯 Exam Tip: Distinguish between the sympathetic and parasympathetic nervous systems by their primary roles: activation vs. rest and digest.

 

Question 4. The gap between two neurons is called _____
(a) synapse
(b) joint
(c) vacuum
Answer: (a) synapse
In simple words: A synapse is the small gap between two neurons where nerve impulses are transmitted from one neuron to another.

🎯 Exam Tip: Knowing the term 'synapse' is fundamental to understanding neuronal communication.

Exercise 1B. Match The Following Pairs.

Question 1.

A	B
1. Thyroxin	a. Pituitary
2. Epinephrine	b. Parathyroid
3. Parathormone	c. Thyroid
4. Androgen	d. Adrenal gland
5. Somatotropin hormones	e. Salivary gland
	f. Sex glands

Answer:

A	B
1. Thyroxin	c. Thyroid
2. Epinephrine	d. Adrenal gland
3. Parathormone	b. Parathyroid
4. Androgen	f. Sex glands
5. Somatotropin hormones	a. Pituitary

In simple words: This table matches key hormones with the glands that produce them, illustrating their specific origins in the endocrine system.

🎯 Exam Tip: Memorizing the association between hormones and their respective glands is essential for questions on the endocrine system.

Exercise 1C. Identify The Odd Item Following Series Of Words.

Question 1. The frontal lobe, Parietal lobe, Thalamus, Occipital lobe
Answer: Thalamus
In simple words: Thalamus is a subcortical structure, while the others (frontal, parietal, occipital lobes) are major cortical lobes of the cerebrum.

🎯 Exam Tip: Knowing the main divisions of the brain, especially cortical lobes vs. subcortical structures, helps in identifying the odd one out.

 

Question 2. Dopamine, Serotonin, Norepinephrine, Uric acid, GABA
Answer: Uric acid
In simple words: Uric acid is a waste product, whereas Dopamine, Serotonin, Norepinephrine, and GABA are all neurotransmitters involved in brain function.

🎯 Exam Tip: Differentiate between neurotransmitters (chemical messengers) and other metabolic compounds to correctly identify the outlier.

 

Question 3. Dendrite, Nucleus, Tectum, Axon, Synapse
Answer: Tectum
In simple words: Dendrite, Nucleus, Axon, and Synapse are all components or parts of a neuron or neuronal communication, while Tectum is a region of the midbrain.

🎯 Exam Tip: A clear understanding of neuronal anatomy versus broader brain structures is key to solving such questions.

 

Question 4. Knee jerk, Sneezing, Thinking, Blinking of eyes
Answer: Thinking
In simple words: Knee jerk, sneezing, and blinking of eyes are involuntary reflex actions, while thinking is a voluntary and complex cognitive process.

🎯 Exam Tip: Distinguish between automatic reflex actions and conscious, voluntary cognitive processes to find the correct answer.

 

Question 5. Thyroid, Sweat glands, Adrenal gland, Gonads, Pituitary gland
Answer: Sweat glands
In simple words: Sweat glands are exocrine glands, secreting substances onto a surface via ducts, whereas the others (Thyroid, Adrenal, Gonads, Pituitary) are endocrine glands, secreting hormones directly into the bloodstream.

🎯 Exam Tip: Understand the difference between exocrine glands (with ducts) and endocrine glands (ductless) when categorizing glands.

Exercise 1D. Identify Which Hormones With Hyposecretion Or Hypersecretion Would Lead To The Following Conditions.

Question 1. Abnormal height, gigantism
Answer: Hypersecretion - Somatotropin
In simple words: Gigantism, characterized by abnormal height, results from the excessive secretion of growth hormone (somatotropin) during childhood.

🎯 Exam Tip: Associate 'hypersecretion' with 'excess' and 'hyposecretion' with 'deficiency' for endocrine disorders.

 

Question 2. Hyperactivity, speedy metabolism.
Answer: Hypersecretion - Thyroxin
In simple words: Increased activity and a faster metabolism are symptoms of hypersecretion of thyroxin, the thyroid hormone.

🎯 Exam Tip: Thyroxin directly impacts metabolic rate, so its excess or deficiency has clear metabolic consequences.

 

Question 3. Cretinism
Answer: Hyposecretion - Thyroxin
In simple words: Cretinism, a condition affecting physical and mental development, is caused by insufficient secretion of thyroxin, especially during early development.

🎯 Exam Tip: Remember cretinism as a specific developmental disorder linked to thyroxin deficiency in infancy.

 

Question 4. Stunted growth, dwarfism
Answer: Hyposecretion - Somatotropin
In simple words: Dwarfism, characterized by stunted growth, is caused by insufficient secretion of growth hormone (somatotropin) during childhood.

🎯 Exam Tip: Connect 'somatotropin' directly to growth and its deficiency to conditions like dwarfism.

 

Question 5. Myxedema, fatigue, sluggishness, depression
Answer: Hyposecretion - Thyroxin
In simple words: Myxedema and related symptoms like fatigue and sluggishness are indicative of severe hypothyroidism, meaning insufficient thyroxin production in adults.

🎯 Exam Tip: Myxedema is an adult form of hypothyroidism with a distinct set of symptoms related to slowed metabolism.

 

Question 6. Increased appetite, overactivity, restlessness, lack of concentration
Answer: Hyposecretion - Insulin, and glycogen
In simple words: These symptoms can be associated with imbalances in blood sugar regulation due to hyposecretion of insulin or glycogen, leading to conditions like diabetes if not properly regulated.

🎯 Exam Tip: Understand that insulin and glycogen work antagonistically to regulate blood sugar, and imbalances can lead to a range of physical and mental symptoms.

2. Which Part Of The Brain Is Involved In Processing The Following Information?

Question 1. Smelling a flower
Answer: Occipital lobe
In simple words: While olfaction primarily involves the olfactory bulb and temporal lobe, the occipital lobe is mainly responsible for visual processing; thus, smelling a flower directly involves primary olfactory cortex (temporal lobe) and not occipital lobe. (Correction to original answer for accuracy)

🎯 Exam Tip: Be precise about sensory processing locations; the olfactory bulb and temporal lobe are crucial for smell, while the occipital lobe is for vision.

 

Question 2. Maintaining balance while standing upright
Answer: Cerebellum
In simple words: The cerebellum is a key brain structure responsible for coordinating voluntary movements, posture, balance, and speech.

🎯 Exam Tip: The cerebellum's role in balance and motor coordination is a frequently tested concept.

 

Question 3. Comprehending a speech
Answer: Temporal Lobe
In simple words: The temporal lobe, specifically Wernicke's area, is crucial for processing auditory information and understanding spoken language.

🎯 Exam Tip: Remember the temporal lobe's association with auditory processing and language comprehension, especially Wernicke's area.

 

Question 4. Memorizing a childhood experience
Answer: Frontal lobe
In simple words: The frontal lobe is heavily involved in memory formation, retrieval, and executive functions like planning and decision-making, including recalling past experiences.

🎯 Exam Tip: The frontal lobe's role extends beyond motor control to complex cognitive functions, including aspects of memory.

 

Question 5. Feeling touch
Answer: Parietal lobe
In simple words: The parietal lobe contains the somatosensory cortex, which is primarily responsible for processing sensory information such as touch, pressure, pain, and temperature.

🎯 Exam Tip: The parietal lobe is the main cortical area for integrating somatosensory information.

 

Question 6. Seeing a picture
Answer: Occipital lobe
In simple words: The occipital lobe, located at the back of the brain, is the primary visual processing center, essential for interpreting what we see.

🎯 Exam Tip: The occipital lobe is dedicated to visual processing; any task involving sight will engage this area.

 

Question 7. Feeling hungry
Answer: Hypothalamus
In simple words: The hypothalamus is a vital brain region that regulates basic bodily functions, including hunger, thirst, and body temperature.

🎯 Exam Tip: The hypothalamus is a key regulator of homeostasis and essential drives like hunger and thirst.

 

Question 8. Feeling afraid
Answer: Amygdala
In simple words: The amygdala is a small, almond-shaped structure in the temporal lobe that plays a central role in processing emotions, particularly fear and anxiety.

🎯 Exam Tip: The amygdala is strongly linked to emotional responses, especially fear, and its function is important for understanding emotional behavior.

3. Answer The Following Questions In 35 To 40 Words.

Question 1. Explain the functions of the hypothalamus.
Answer:

• Hypothalamus controls major bodily needs i.e., primary needs of an individual like hunger, thirst, sex as well as temperature regulation, and sleep.
• It is also called the pleasure center of our body.

In simple words: The hypothalamus is a vital brain region that regulates fundamental drives like hunger, thirst, and sex, maintains body temperature, and influences sleep-wake cycles, also contributing to feelings of pleasure.

🎯 Exam Tip: Focus on the hypothalamus's role in maintaining homeostasis and regulating basic survival needs.

 

Question 2. Describe the functions of each of the four lobes.
Answer:

• Frontal lobe: It controls motor actions, thinking, memory and reasoning. It has Broca's area which helps in speech production.
• Parietal lobe: It helps in understanding information regarding skin-like touch, pressure, pain, and temperature.
• Occipital lobe: It is the visual processing center. It controls the sense of hearing, smell, and taste. It has Wernicke's area which helps in language understanding.
• Temporal Lobe: Hearing, understanding language, memory for language take place because of the temporal lobe.

In simple words: The frontal lobe handles planning and movement, the parietal lobe processes sensory input like touch, the occipital lobe is for vision, and the temporal lobe manages hearing and language comprehension.

🎯 Exam Tip: Clearly differentiate the primary functions of each lobe, particularly their sensory and motor roles, and associated language areas.

 

Question 3. Explain the functions of the Amygdala and Hippocampus.
Answer:

• Amygdala: It stores emotional memories of experiences. We experience emotions, especially fear due to the amygdala.
• Hippocampus: It is the storage of long-term memories. If a person gets Alzheimer's disease, his hippocampus is. mainly affected.

In simple words: The amygdala processes emotions, especially fear, and stores emotional memories, while the hippocampus is critical for the formation of new long-term memories.

🎯 Exam Tip: Understand the distinct but complementary roles of the amygdala (emotion) and hippocampus (memory) within the limbic system.

 

Question 4. What is a synapse? How does a nerve impulse travel from one to another neuron?
Answer:

• A synapse is a gap between two neurons.
• The nerve impulse or neural message jumps across the synapse in order to reach the dendrite of another neuron.
• When the neural message is passing through, it excites or inhibits the neurotransmitter in it. This chemical reaction decides our reaction to various situations.

In simple words: A synapse is the junction between neurons where electrical signals are converted into chemical signals (neurotransmitters) to transmit information to the next neuron, causing excitation or inhibition.

🎯 Exam Tip: Focus on the chemical nature of synaptic transmission and the role of neurotransmitters in relaying signals.

 

Question 5. Which are the important parts of the hindbrain? Explain their functions.
Answer: Important parts of the hindbrain and their functions are as follows:

• Cerebellum: It helps in maintaining body posture and body balance. It also helps in the coordination of the movements.
• Brain stem: Medulla oblongata controls the breathing rate, pulse rate, blood pressure, and digestion. Pons sends and receives information from the lower parts of the brain. It helps to transmit messages between the cerebellum and cortex.
• Reticular activation system: Its main function is to maintain wakefulness, concentration, and alertness.

In simple words: The hindbrain includes the cerebellum for balance and movement coordination, the brain stem (medulla and pons) for vital involuntary functions and information relay, and the reticular activation system for alertness.

🎯 Exam Tip: Remember that the hindbrain primarily controls vital, unconscious functions and motor coordination essential for survival.

 

Question 6. How do endocrine glands affect our behaviour?
Answer:

• Endocrine glands secrete chemical substances called hormones.
• Hormones are like messengers that are responsible for certain behaviours or the absence of reactions.
• e.g. Thyroid gland secretes the thyroxin hormone. Its hypersecretion leads to Grave's disease while hyposecretion results in cretinism or myxedema.

In simple words: Endocrine glands release hormones that act as chemical messengers, influencing various bodily functions and, consequently, our behavior, with imbalances leading to specific conditions like hyper- or hypothyroidism.

🎯 Exam Tip: Understand hormones as key regulators that directly influence mood, metabolism, and physical states, thereby impacting overall behavior.

4. Write Short Notes.

Question 1. Autonomic Nervous System
Answer:

• The autonomic nervous system controls the internal activities of the human body including heart rate, breathing, digestion, disposal of waste products, and toxins.
• It is divided into the sympathetic and parasympathetic nervous systems.
• The sympathetic nervous system prepares our body to face stressful and threatening situations. It prepares us for a 'flight or fight reaction. The job of the system is just opposite to its name.
• The parasympathetic nervous system takes over when the situation becomes normal. It directs our body to store energy for emergencies.

In simple words: The Autonomic Nervous System (ANS) involuntarily regulates internal body functions like heart rate and digestion, splitting into the sympathetic (fight or flight) and parasympathetic (rest and digest) divisions to maintain balance.

🎯 Exam Tip: Clearly define the two subdivisions of the ANS and their contrasting roles in maintaining bodily equilibrium.

 

Question 2. Limbic System
Answer: One of the important parts of the brain is the limbic system.

• Hippocampus, amygdala, thalamus, and hypothalamus are parts of the limbic system.
• Hippocampus is responsible for the storage of long-term memories.
• Amygdala stores emotional memories of our experiences.
• Thalamus is called a relay station of the brain. It receives all information from the body and sends it to various parts of the brain.
• Hypothalamus controls major bodily needs like hunger, thirst, sex as well as temperature regulation, and sleep.

In simple words: The limbic system, comprising structures like the hippocampus, amygdala, thalamus, and hypothalamus, is a crucial brain network involved in processing emotions, memory, and fundamental drives.

🎯 Exam Tip: Focus on the key components of the limbic system and their collective role in emotion, motivation, and memory formation.

 

Question 3. Neurotransmitters
Answer: Neurotransmitters are chemical messengers. The important neurotransmitters are:

• Acetylcholine: It is a chemical released by motor neurons of the nervous system to activate muscles.
• Dopamine: It is released by the brain. If the level of dopamine is normal, we experience happy, pleasant feelings. It also plays an important role in the motivational process.
• Norepinephrine: It increases the force of skeletal muscles, especially during fight or flight response.
• Serotonin: It plays a role mainly in cognition, reward, learning, and memory It also controls wakefulness, sleep, hunger, thirst, and liking.
• Glutamate: It helps in learning, memory, and maintaining sugar levels.
• GABA (Gama Amino Butyric Acid): It is the chief inhibitory neurotransmitter i.e. its principal role is to reduce the excitability of neurons throughout the nervous system. If it is less, it leads to convulsions and we cannot control body movements.

In simple words: Neurotransmitters are chemical signals that transmit messages between neurons, influencing various functions like muscle movement, mood, motivation, memory, and alertness.

🎯 Exam Tip: Be able to name a few major neurotransmitters and associate them with their primary functions or effects on behavior and physiology.

 

Question 4. Pituitary gland
Answer:

• The pituitary gland is one of the endocrine glands, i.e., glands that secrete chemical substances into the bloodstream.
• It is also called as master gland as it helps other glands to produce their secretions and secretes the majority of hormones.
• It consists of the anterior lobe and posterior lobe.
• Anterior lobe: It secretes somatotropin, growth hormone, and adrenocorticotropic hormone. It helps the growth of the body and aids the adrenal gland. The hormones secreted by this gland are also vital for the nourishment of foetus.
• Hypo or hypersecretion in the anterior lobe: Hyposecretion leads to dwarfism, wherein a person is very short (two-three feet tall). On the other hand, hypersecretion can lead to gigantism, wherein a person becomes very huge and is eight-nine feet tall. Hypersecretion can also result in acromegaly, wherein a person has the features of a chimpanzee.
• Posterior lobe: It secretes oxytocin (which creates a feeling of happiness), pituitrin (which helps smooth muscle functioning of the stomach), thyrotrophic follicle-stimulating luteinizing hormone (which helps in the nourishment of foetus), and endorphins (which help to create neurotransmitters).

In simple words: The pituitary gland, often called the "master gland," regulates other endocrine glands and secretes hormones vital for growth, reproduction, and overall bodily function through its anterior and posterior lobes.

🎯 Exam Tip: Remember the pituitary's role as the "master gland" and be aware of the key hormones secreted by its anterior and posterior lobes, along with their effects. (Note: Luteinizing hormone and FSH are from the anterior pituitary, and oxytocin and vasopressin are released from posterior, but produced in hypothalamus. The description for posterior lobe also mentions thyrotrophic FSH/LH and endorphins which are typically anterior pituitary or other sources, ensure to align with textbook knowledge.)

5. Compare And Contrast

Question 1. Sympathetic nervous system and Parasympathetic nervous system
Answer:

• The sympathetic nervous system prepares our body to face stressful and threatening situations. It prepares us for a 'flight or fight reaction. On the other hand, the parasympathetic nervous system takes over when the situation becomes normal,
• Example:
• Situation: Suppose you are chased by a dog.
• Sympathetic nervous system: Due to the functioning of this system, your heartbeat and palpitation increase. You also start to sweat.
• Parasympathetic nervous system: When PNS takes over, your heart rate, palpitation, and sweating become normal. You regain a cool and composed state due to the functioning of this system.

In simple words: The sympathetic nervous system primes the body for action (fight or flight) during stress, increasing heart rate and alertness, while the parasympathetic nervous system promotes relaxation and energy conservation (rest and digest) after the threat passes.

🎯 Exam Tip: Focus on the antagonistic nature of these two systems and provide clear examples of their opposing effects on body functions.

 

Question 2. Exocrine glands and Endocrine glands
Answer:

• Exocrine glands directly release their secretions into the organ or tissue while endocrine glands secrete chemical substances into the bloodstream.
• Exocrine glands have separate ducts for their secretion and so, they are also called duct glands, e.g. sweat glands and tear glands. On the other hand, endocrine glands are called ductless glands as they don't have a separate duct. e.g. pituitary gland and thyroid gland.

In simple words: Exocrine glands release secretions through ducts onto body surfaces or into cavities (e.g., sweat glands), while endocrine glands release hormones directly into the bloodstream without ducts (e.g., thyroid gland).

🎯 Exam Tip: The key differentiator is the presence (exocrine) or absence (endocrine) of ducts for secretion delivery.

6. Answer In 150-200 Words.

Question 1. Explain the functions of various parts of the human brain.
Answer: The brain consists of three major parts, viz. hindbrain, midbrain, and forebrain. Its functions are as follows:
(i) Hindbrain

• Cerebellum: It helps in maintaining body posture and balance as well as aids in the coordination of movements.
• Brain stem: Medulla oblongata controls the breathing rate, pulse rate, blood pressure, and digestion. Pons helps to transmit messages between the cerebellum and cortex.
• Reticular activation system: It is the 'Alarm clock' of the body. It maintains wakefulness, concentration, and alertness.

(ii) Midbrain: It sends information to the upper part of the brain and controls eye movements.

(iii) Forebrain

• Cerebrum: Cerebral cortex controls higher-order mental processes such as attention, perception, learning, memory. The surface of the cerebral cortex is divided into right and left hemispheres. Neurons from the right hemisphere control the left side of the body and vice versa. Left hemisphere controls language, spatial relation, and pattern recognition.
• Four lobes: Frontal lobe controls motor actions, thinking, memory and reasoning. The parietal lobe helps us in understanding information regarding skin. The occipital lobe controls our vision. The temporal lobe is responsible for hearing, understanding language, and memory for language.

In simple words: The brain is structured into the hindbrain (controlling vital functions, balance, and alertness), midbrain (relaying sensory and motor information, eye movements), and forebrain (responsible for higher cognitive functions, conscious thought, memory, and sensory processing across its various lobes).

🎯 Exam Tip: Organize your answer by the three main brain divisions (hindbrain, midbrain, forebrain) and list specific structures and their functions within each, emphasizing their contributions to overall brain activity.

 

Question 2. Explain the significance of endocrine glands in human behaviour. State the functions of any five endocrine glands in detail.
Answer:

• Endocrine glands secrete vital chemical substances called hormones. There is a strong impact of hormones upon human behavior.
• Hormones are responsible for certain behaviours or the absence of reactions.
• Over (hyper) or under (hypo) secretion of hormones may lead to a variety of problems.
• e.g. Hypersecretion of insulin and glycogen hormones by the pancreas reduces blood sugar levels. It results in hyperglycemia, wherein a person lacks energy and motivation, may faint and go to coma. Conversely, in the case of hyposecretion, a person gets diabetes. He becomes quite hungry and feels very tired and restless. He also shows irritated behaviour and faces frequent and uncontrolled urination.

The functions of the five endocrine glands are as follows:

• Thyroid gland: It secretes thyroxin which maintains the rate of metabolism.
• Parathyroid gland: It secretes parathyroxin which maintains calcium as well as phosphate balance.
• Pancreas: It secretes insulin and glycogen that is responsible for maintaining blood sugar levels.
• Adrenal gland: Cortex secretes cortin or cortisone which maintains the level of water, sugar, and sodium. The medulla secretes adrenalin (which is associated with fear) and noradrenaline (which is associated with anger). Medulla plays important role in emotional excitement.
• Gonads (sex gland): Testes in males secrete androgen and testosterone. These hormones are responsible for secondary sex characteristics in males. Their voice becomes hoarse. They also get mustaches and beards. Ovaries in females secrete estrogen and progesterone. These hormones are responsible for secondary sex characteristics in females. As a result, feminine looks develop and menarche begins.

In simple words: Endocrine glands produce hormones that significantly influence human behavior by regulating mood, energy, stress responses, and physical development; imbalances can lead to distinct behavioral and physiological conditions. Specific glands like thyroid, parathyroid, pancreas, adrenals, and gonads each play crucial roles in metabolism, calcium balance, blood sugar, stress response, and sexual development.

🎯 Exam Tip: When discussing endocrine glands, emphasize the role of hormones as chemical messengers and illustrate their impact with examples of specific glands and the consequences of their hypo- or hypersecretion on behavior and body functions.

Activities

Activity 1 (Textbook Page No. 76)

Few activities are given below. Identify the system which dominates during these activities.
1. Picking up an object from the ground
2. Shivering when we sense danger
3. Feeling composed when we feel safe
4. Increase in heart rate when we sense that we are going to meet with an accident
Answer:
1. Central nervous system
2. Sympathetic nervous system
3. Parasympathetic nervous system
4. Sympathetic nervous system
In simple words: This activity categorizes various bodily responses into their dominant nervous system controls: voluntary actions (CNS), stress responses (sympathetic), and relaxation (parasympathetic).

🎯 Exam Tip: Understand the distinction between voluntary actions controlled by the Central Nervous System and involuntary responses managed by the Autonomic Nervous System's sympathetic and parasympathetic branches.

Activity 2 (Textbook Page No. 80)

Think of the following actions. Which of them would be reflex actions and which of them will not be reflex actions?
- Throwing a ball in a cricket match
- Closing the eyes if someone brings a finger too close to them.
- Removing the hand when you accidentally touch a thorn.
- Immediate movement of the knee when tapped just below it.
- Touching a hot object and pulling back your hand.
Answer:
Reflex actions:
- Closing the eyes if someone brings a finger too close to them.
- Removing the hand when you accidentally touch a thorn.
- Immediate movement of the knee when tapped just below it.
- Touching a hot object and pulling back your hand.
Non-reflex actions:
- Throwing a ball in a cricket match
In simple words: Reflex actions are automatic, involuntary responses to stimuli, like blinking or pulling away from heat, while non-reflex actions are voluntary and require conscious thought and control, such as throwing a ball.

🎯 Exam Tip: Differentiate reflex actions (involuntary, rapid, protective) from voluntary actions (conscious, controlled, often learned) by their nature and neural pathways.