31 Years NEET Previous Year Questions: Neural Control & Coordination Free

• A. Schwann cells: Schwann cells are responsible for the formation of the myelin sheath around neurons in the peripheral nervous system. Thus, A corresponds to III (Myelin Sheath).
• B. Synaptic knob: The synaptic knob is the part of a neuron that releases neurotransmitters into the synapse to transmit nerve signals to the next neuron. Thus, B corresponds to I (Neurotransmitter).
• C. Bipolar neurons: Bipolar neurons are primarily found in the retina, where they play a role in visual processing. Thus, C corresponds to IV (Retina).
• D. Multipolar neurons: Multipolar neurons are found in the cerebral cortex, where they play a key role in complex brain functions. Thus, D corresponds to II (Cerebral cortex).

Thus, the correct match is:

• A-III: Schwann cells form the myelin sheath.
• B-I: Synaptic knobs release neurotransmitters.
• C-IV: Bipolar neurons are found in the retina.
• D-II: Multipolar neurons are found in the cerebral cortex.

• A. Limbic system: The limbic system is involved in emotions, and the amygdala is a major component of the limbic system, which plays a key role in emotional responses. Thus, A corresponds to III (Amygdala).
• B. Arachnoid: The arachnoid is one of the cranial meninges (protective layers surrounding the brain). Therefore, B corresponds to IV (Cranial meninge).
• C. Corpus callosum: The corpus callosum is a tract of nerve fibers that connects the two cerebral hemispheres, allowing communication between them. Thus, C corresponds to II (Tract of nerve fibres).
• D. Hypothalamus: The hypothalamus is involved in regulating various physiological processes such as body temperature. Therefore, D corresponds to I (Body temperature).

Thus, the correct match is:

• A-III: Limbic system is related to the amygdala.
• B-IV: Arachnoid is a cranial meninge.
• C-II: Corpus callosum is a tract of nerve fibres.
• D-I: Hypothalamus regulates body temperature.

• Statement I describes the corpus callosum, a structure in the brain. The corpus callosum is a large bundle of nerve fibers that connects the two cerebral hemispheres, allowing for communication between them. This statement is correct.
• Statement II mentions the brain stem and lists its components as the medulla oblongata, pons, and cerebrum. The error here is in including the cerebrum as part of the brain stem. In actuality, the brain stem consists of the medulla oblongata, the pons, and the midbrain, not the cerebrum. The cerebrum is part of the forebrain and is responsible for higher cognitive functions such as thinking, perceiving, planning, and understanding language. Therefore, Statement II is incorrect.

Topic in NCERT: HindBrain
Line in NCERT: "The hemispheres are connected by a tract of nerve fibres called corpus callosum. Three major regions make up the brain stem; mid brain, pons and medulla oblongata."

To match List I with List II correctly, we start by identifying the function of each brain region described in List I and match these descriptions to the corresponding functions stated in List II:

• Pons: The pons is part of the brainstem located between the midbrain and the medulla oblongata. It principally acts as a bridge connecting various parts of the brain, and it is also involved in controlling essential functions like sleep and respiration.
• Hypothalamus: The hypothalamus is a small portion at the base of the brain that plays a crucial role in hormone release and regulation of essential bodily functions, including temperature control, thirst, hunger, sleep, mood, and sexual behavior. It contains several neurosecretory cells that produce hormones.
• Medulla: The medulla oblongata, also part of the brainstem, primarily controls autonomic functions such as breathing, heart rate, and digestion (including gastric secretions).
• Cerebellum: The cerebellum is located at the back of the brain and is responsible for controlling motor skills, balance, coordination, and posture. It helps refine the movements dictated by the motor cortex.

Now, let's match these descriptions to those listed in List II:
A. Pons should match with "Connects different regions of the brain." - this corresponds to III.
B. Hypothalamus should match with "Neurosecretory cells." - this corresponds to IV.
C. Medulla should match with "Controls respiration and gastric secretions." - this corresponds to II.
D. Cerebellum should match with "Provides additional space for Neurons, regulates posture and balance." - this corresponds to I.

When we look at the given options:
Option A: A-II, B-III, C-I, D-IV (wrong)
Option B: A-III, B-IV, C-II, D-I (correct)
Option C: A-I, B-III, C-II, D-IV (wrong)
Option D: A-II, B-I, C-III, D-IV (wrong)

The correct answer is Option B: A-III, B-IV, C-II, D-I.

• The limbic system, which includes structures such as the amygdala and hippocampus, plays a significant role in regulating emotions, including fear, pleasure, and anger. The hypothalamus, another component of the limbic system, is involved in various functions, including the regulation of sexual behavior and responses to pleasure and excitement. Therefore, option D is correct.
• Option (A), (B) and (C) are not correct because corpora quadrigemina is a part of the midbrain and consists of four round swellings. Corpus callosum is a tract of nerve fibres that connects right and left cerebral hemispheres. Thalamus is a major coordinating centre in the forebrain for sensory and motor signalling. Midbrain, pons and medulla oblongata together form the brain stem.

Topic in NCERT: Limbic System

Line in NCERT: "the limbic system which is concerned with olfaction, autonomic responses, regulation of sexual behaviour, expression of emotional reactions, and motivation."

Option (a) is the correct answer because
(a) Multipolar neurons are present in cerebral cortex.
(b) Bipolar neurons are found in the retina of the eye.
(c) Myelinated nerve fibres are found in spinal and cranial nerves
(d) Unmyelinated nerve fibres are commonly found in autonomous and somatic neural systems.

Option (c) is the correct answer as impulse transmission across an electrical synapse is always faster than that across a chemical synapse.

• Chemical synapses use chemicals for transmission which are known as neurotransmitters.
• The membranes of presynaptic and postsynaptic neurons are in close proximity in an electrical synapse.
• In an electrical synapse, the transmission of the impulse occurs in the form of an electrical current from one neuron to the next neuron.