All questions of Neural Control and Coordination for NEET Exam

Option A is correct becose, corpus callosam is trancverce connection between two cerebral hemisphears.. it helps in coordination between the two cerebral hemisphears..

Correct answer is option.b multipolar

Brainstem: The Support System of Brain
The brainstem is the lower part of the brain that connects the brain to the spinal cord. It is responsible for regulating important functions such as breathing, heart rate, blood pressure, and consciousness. The brainstem consists of three main parts, which are:

Medulla
The medulla oblongata, or simply the medulla, is the lowest part of the brainstem. It controls involuntary functions such as breathing, heartbeat, and digestion. The medulla also contains reflex centers for coughing, sneezing, and vomiting.

Pons
The pons is the middle part of the brainstem, located above the medulla and below the midbrain. It is involved in the regulation of sleep, respiration, and posture. The pons also helps to relay messages between different parts of the brain.

Midbrain
The midbrain, also known as the mesencephalon, is the uppermost part of the brainstem. It is involved in the regulation of vision, hearing, and movement. The midbrain contains several important structures, including the substantia nigra, which produces dopamine and is involved in the control of movement.

Conclusion
In conclusion, the brainstem is the support system of the brain and is responsible for regulating vital functions. It consists of three main parts, which are the medulla, pons, and midbrain. The medulla controls involuntary functions such as breathing and heartbeat, the pons is involved in the regulation of sleep and posture, and the midbrain is responsible for vision, hearing, and movement.

The primary function of the hypothalamus is homoeostasis, which is to maintain the body's normal temperature and body's status. So, if there is an injury to the hypothalamus, the thermoregulatory centre is disturbed resulting in a deregulation of body temperature. So, the correct answer is option D.

Total sum of physio-electrochemical changes that takes place along the length of nerve fibre is known as nerve impulse. Change in potential due to stimulation of nerve fibre is called action potential. During propagation of nerve impulse, Na⁺ enters inside so(+ve) change is formed inside the membrane. K⁺ ions come out.

Axon transmit impulses away from cellbody to a synapse or to a neuro muscular junction.(11th ncert page no 317 .5th line)

Neurilemma (also known as neurolemma, sheath of Schwann, or Schwann's sheath) is the outermost nucleated cytoplasmic layer of Schwann cells (also called neurilemmocytes) that surrounds the axon of the neuron. It forms the outermost layer of the nerve fiber in the peripheral nervous system.

The part of the brain that connects the two hemispheres of the brain is called the corpus callosum. It contains a bundle of neuronal fibers found in humans and other higher order mammals that allow the two hemispheres to talk to one another.

Understanding Resting Potential
The resting potential refers to the electrical charge difference across the neuronal membrane when a neuron is not actively firing an action potential. This potential is crucial for the transmission of signals in the nervous system.
Key Concepts of Resting Potential
- Electrochemical Gradient:
- The difference in concentration of ions (like Na+ and K+) across the membrane creates an electrochemical gradient.
- This gradient is essential for maintaining the resting potential.
- Electrical Potential:
- The term "electrical potential" specifically refers to the voltage difference across a membrane.
- In a resting neuron, this electrical potential typically ranges from -70 to -90 mV.
- Importance of Ions:
- Potassium ions (K+) are more concentrated inside the cell, while sodium ions (Na+) are more concentrated outside.
- The selective permeability of the membrane to K+ contributes significantly to the resting potential.
- Membrane Channels:
- Ion channels, particularly potassium channels, allow K+ to exit the cell more freely, leading to a negative charge inside the cell compared to the outside.
Conclusion
The correct answer is "B) Electrical potential" as it directly describes the voltage difference across the neuronal membrane during the resting state. Understanding this concept is pivotal for grasping how neurons communicate and respond to stimuli, forming the basis for further studies in neurobiology and physiology.

Understanding the Role of CNS and PNS in Physical Exercise
During intense physical exercise, the coordination between the central nervous system (CNS) and peripheral nervous system (PNS) is vital for maintaining homeostasis and ensuring efficient body function.
Functions of the CNS
- The CNS is responsible for processing sensory information from various sources, including muscles and organs.
- It generates appropriate motor responses by sending efferent impulses to skeletal muscles, facilitating movement.
- The CNS integrates feedback from the body to adjust physiological responses during exercise, ensuring that the body can meet the demands of physical activity.
Functions of the PNS
- The PNS serves as a communication network between the CNS and the rest of the body.
- It transmits afferent impulses from the organs (like the heart and lungs) back to the CNS, providing critical feedback on the body’s state during exercise.
- The PNS also carries efferent signals to involuntary organs, regulating heart rate and respiration, which are crucial for sustaining energy levels and oxygen supply during intense workouts.
Coordination for Homeostasis
- Together, the CNS and PNS work synergistically to maintain homeostasis during physical exertion.
- The CNS processes information and adjusts body functions, while the PNS ensures that feedback loops function effectively, allowing for real-time adjustments to heart rate and muscle contractions.
In summary, option D accurately describes how the CNS and PNS collaborate to manage the body’s response to exercise, ensuring that both voluntary and involuntary functions are well-coordinated for optimal performance and safety.

Understanding the Somatic Neural System
The assertion and reason provided in the question relate to the functions of the somatic and autonomic nervous systems.
Assertion Explained
- The somatic neural system primarily controls voluntary functions.
- It is responsible for movements of skeletal muscles, allowing conscious control over these actions.
Reason Clarification
- The somatic neural system is not divided into sympathetic and parasympathetic systems.
- Instead, these divisions belong to the autonomic nervous system, which regulates involuntary functions such as heart rate, digestion, and respiratory rate.
Correctness of Assertion and Reason
- The assertion is incorrect because it states that the somatic neural system regulates involuntary functions, which is not true.
- The reason is also incorrect because it misidentifies the components of the nervous system.
Conclusion
Given that both the assertion and reason are incorrect, the answer to the question is option 'D':
- Both Assertion and Reason are incorrect.
This understanding is crucial for students preparing for exams like NEET, as it highlights the distinctions between the somatic and autonomic nervous systems.

Understanding the Somatic Neural System
The somatic neural system plays a crucial role in controlling voluntary movements by transmitting impulses to skeletal muscles. Here's a deeper look into this system:
Function of the Somatic Neural System
- The somatic nervous system is responsible for carrying sensory and motor information to and from the central nervous system (CNS).
- It governs voluntary control over skeletal muscles, enabling movements such as walking, writing, and speaking.

Components of the Somatic Neural System
- Motor Neurons: These neurons originate in the CNS and extend out to skeletal muscles, where they release neurotransmitters to facilitate muscle contraction.
- Sensory Neurons: They relay information from sensory receptors (like touch, pain, and temperature) back to the CNS, helping to coordinate movements.
Comparison with Other Neural Systems
- Autonomic Neural System: This system controls involuntary actions, such as heart rate and digestion, and does not involve skeletal muscle.
- Central Neural System: Comprises the brain and spinal cord but does not directly transmit impulses to muscles.
- Peripheral Neural System: Encompasses both the somatic and autonomic systems, but the somatic specifically targets skeletal muscles.
Conclusion
In summary, the somatic neural system is integral for voluntary muscle control, making it the correct answer to the question regarding the transmission of impulses to skeletal muscles. Understanding this system is essential for grasping how movements are coordinated in the human body, particularly in contexts such as NEET preparation.

Incorrect Statements about Electrical Synapse:

Membranes Proximity:
- Statement (i) is incorrect because at electrical synapses, the membranes of pre and post synaptic neurons are in direct contact, not just in close proximity.

Direct Current Flow:
- Statement (ii) is correct as electrical current can flow directly from one neuron into the other across the synapses.

Impulse Transmission:
- Statement (iii) is incorrect as the transmission of an impulse across electrical synapses is not similar to impulse conduction along a single axon. It is faster and more direct.

Use of Ach:
- Statement (iv) is incorrect because electrical synapses do not pass electrical signals between cells using acetylcholine (Ach) or any other neurotransmitter.

Speed of Transmission:
- Statement (v) is correct as electrical synapses are known for their fast transmission of signals between neurons.

Prevalence of Electrical Synapses:
- Statement (vi) is incorrect as electrical synapses are actually quite common in the nervous system, especially in regions where rapid signaling is essential.
Therefore, the incorrect statements about electrical synapses are (i), (iii), and (iv), making option (c) the correct choice.

The box enclosing and protecting the brain is called as the cranium . The cranium is the part of the skull, that encloses the brain. Therefore option A is the correct answer.

Cerebellum is a part of the brain and is responsible for motor control which includes muscle movement , equilibrium and balance as it relates to movement .
So 'a' is correct.

Connection Between Hemispheres
The structure that connects the two hemispheres of the cerebrum is the Corpus Callosum. This large bundle of nerve fibers plays a crucial role in interhemispheric communication.
Function of the Corpus Callosum
- Communication: It facilitates communication between the left and right hemispheres, allowing for the integration of sensory information and coordination of motor functions.
- Transfer of Information: It enables the transfer of information from one hemisphere to the other, aiding in tasks that require cooperation between both sides of the brain.
Structure of the Corpus Callosum
- Anatomy: The corpus callosum is a C-shaped structure located beneath the cerebral cortex. It consists of over 200 million axons that connect corresponding regions of the two hemispheres.
- Regions: It can be divided into four parts: the rostrum, genu, body, and splenium, each connecting different areas of the brain.
Importance in Brain Function
- Cognitive Functions: The corpus callosum is essential for higher cognitive functions such as problem-solving, language, and spatial awareness.
- Motor Coordination: It plays a vital role in coordinating movements that involve both sides of the body, ensuring they work together seamlessly.
In summary, the corpus callosum is essential for integrating the functions of the left and right hemispheres, making it a critical structure for overall brain function and coordination.

Short Repeatedly Branched Fibres: Axon

An axon is a long, slender projection of a neuron that conducts electrical impulses away from the cell body, towards other neurons or target cells. It is the primary transmission line of the nervous system, responsible for transmitting and propagating action potentials.

Structure of an Axon:
- Axon Hillock: The axon hillock is the cone-shaped region of the neuron where the axon originates from the cell body. It is the site where action potentials are generated.
- Axon Proper: The axon proper is the elongated part of the axon that extends away from the cell body. It is covered by a lipid-rich insulating layer called the myelin sheath, which is produced by specialized supporting cells called Schwann cells in the peripheral nervous system, and oligodendrocytes in the central nervous system.
- Axon Terminal: At the distal end of the axon, there are fine branches called axon terminals or terminal boutons. These branches form synapses with other neurons or target cells, allowing for the transmission of signals.

Function of an Axon:
- Signal Transmission: The main function of an axon is to transmit electrical signals, known as action potentials, from the cell body to other neurons or target cells. These signals travel along the axon, facilitated by the myelin sheath and nodes of Ranvier, which allow for saltatory conduction. This rapid transmission of signals enables efficient communication within the nervous system.
- Synaptic Transmission: At the axon terminals, the electrical signals are converted into chemical signals. When an action potential reaches the axon terminal, it triggers the release of neurotransmitters into the synaptic cleft, which then bind to receptors on the target cell, transmitting the signal from one neuron to another or to an effector cell (such as a muscle cell or gland).

Conclusion:
In summary, the short repeatedly branched fibers in neurons are called axons. Axons play a vital role in the transmission of electrical signals throughout the nervous system, allowing for communication between neurons and the activation of target cells.

This is the time during which another stimulus given to the neuron (no matter how strong) will not lead to a second action potential. Thus, because Na+ channels are inactivated during this time, additional depolarizing stimuli do not lead to new action potentials. The absolute refractory period takes about 1-2 ms. refractory period is a period of time during which an organ or cell is incapable of repeating a particular action, or (more precisely) the amount of time it takes for an excitable membrane to be ready for a second stimulus once it returns to its resting state following an excitation. It most commonly refers to electrically excitable muscle cells or neurons. Absolute refractory period corresponds to depolarization and repolarization, whereas relative refractory period corresponds to hyperpolarization.

Assertion: Role of the Human Brain
The assertion states that the human brain functions as the primary control center for both voluntary and involuntary actions. This is indeed true. The brain is responsible for:
- Voluntary Actions: Such as walking, talking, and writing, which involve conscious control.
- Involuntary Actions: Such as heartbeat regulation, breathing, and digestion, which occur without conscious effort.
Reason: Protection of the Brain
The reason provided explains that the brain is protected by the skull and meninges, which are crucial for safeguarding it against physical damage. This statement is also true as:
- Skull: The bony structure encases the brain, providing a hard barrier against external impacts.
- Meninges: The three protective membranes (dura mater, arachnoid mater, and pia mater) add additional layers of protection, including cushioning and support.
Relationship Between Assertion and Reason
While both statements are true, the reason does not explain why the brain is the control center for actions. The protection of the brain is important for its integrity but does not contribute to its functional role in controlling body actions. Thus:
- The assertion emphasizes the brain's control functions.
- The reason focuses solely on the protective aspects.
Conclusion
Therefore, the correct answer is option 'B': Both Assertion and Reason are true, but Reason is not the correct explanation of Assertion. This demonstrates a common scenario in scientific reasoning, where related truths do not always provide direct explanations of each other.

Understanding Homeostasis
Homeostasis is the process by which living organisms maintain a stable internal environment despite external changes. This involves the regulation of various physiological parameters such as temperature, pH, and electrolyte balance.
Assertion Explanation
- The assertion states that the functions of the organs in our body must be coordinated to maintain homeostasis.
- This is correct because organs do not function in isolation. For example, the respiratory system works with the circulatory system to ensure that oxygen is delivered to tissues and carbon dioxide is removed.
Reason Explanation
- The reason provided indicates that coordination is the interaction and complementing functions of two or more organs.
- This is also a correct statement as organs often work together to perform complex tasks that no single organ could achieve alone. For example, the kidneys and the endocrine system work together to regulate blood pressure and fluid balance.
Linking Assertion and Reason
- The reason directly explains the assertion by highlighting how organs complement each other to maintain homeostasis.
- For instance, during exercise, the heart rate increases (cardiovascular system), while the lungs facilitate increased oxygen intake (respiratory system), showcasing their coordinated efforts to maintain stable conditions in the body.
Conclusion
- Since both the assertion and the reason are true, and the reason correctly explains the assertion, the correct answer is option 'A': Both Assertion and Reason are correct, and Reason is the correct explanation of Assertion.

Understanding the Autonomic Neural System
The autonomic neural system plays a crucial role in managing involuntary actions in the body, including heart rate and digestion. Here's how it works:
Components of the Autonomic Nervous System
- The autonomic nervous system (ANS) is divided into two main branches: the sympathetic and parasympathetic nervous systems.
- Sympathetic Nervous System: Prepares the body for 'fight or flight' responses, increasing heart rate and energy mobilization.
- Parasympathetic Nervous System: Promotes 'rest and digest' functions, decreasing heart rate and enhancing digestive processes.
Functions of the Autonomic Nervous System
- Heart Rate Control: The ANS regulates heart rate through the sympathetic (increases heart rate) and parasympathetic (decreases heart rate) branches, maintaining homeostasis according to the body's needs.
- Digestion Regulation: The parasympathetic system stimulates digestive activities, such as salivation, enzyme secretion, and peristalsis in the intestines.
Contrast with Other Neural Systems
- Somatic Neural System: Controls voluntary movements and skeletal muscles, allowing conscious control over actions like walking or speaking.
- Peripheral Nervous System: Encompasses both the somatic and autonomic systems, but it is not specific to involuntary functions.
In summary, the autonomic neural system (option B) is essential for regulating involuntary actions such as heart rate and digestion, distinguishing it from the somatic and peripheral nervous systems, which are involved in voluntary and broader neural activities, respectively.

Explanation of Statement I
- Statement I: The cerebral hemispheres are connected by a nerve tract known as corpus callosum.
- This statement is correct. The corpus callosum is a thick band of nerve fibers that connects the left and right cerebral hemispheres, facilitating communication between them.
Explanation of Statement II
- Statement II: The brain stem consists of the medulla oblongata, pons, and cerebrum.
- This statement is incorrect. The brain stem is made up of the medulla oblongata, pons, and midbrain, not the cerebrum. The cerebrum is actually a separate structure that is responsible for higher brain functions, including thought and action.
Conclusion
- Given the evaluations of both statements:
- Statement I is correct.
- Statement II is incorrect.
Thus, the correct answer is option C: Statement I is correct but Statement II is incorrect.

The pre-synaptic neuron transmits an impulse to the post-synaptic neuron by releasing neurotransmitters from synaptic vesicles into the synaptic cleft, where they bind to specific receptors on the post-synaptic membrane.

There are different kinds of stimulus that is received by different receptors in our body. Hearing of sound of bell is conditioned stimulus and salivation in response to bell is conditioned response. Food itself is conditioned stimulus and salivation in response to food is unconditioned response.