Nervous System Physiology

It is a type of neuronal support cell (neuroglia) that forms the epithelial lining of the ventricles (cavities) in the brain and the central canal of the spinal cord. 

Corpus callosum is a thick band of nerve fibers that divides the cerebrum into left and right hemispheres. It connects the left and right sides of the brain allowing for communication between both hemispheres. The corpus callosum transfers motor, sensory and cognitive information between the brain hemispheres.

It lies between the cerebral cortex and midbrain. Its prominent function includes relaying sensory and motor signals to the cerebral cortex, along with the regulation of consciousness, sleep and alertness. Impulses originated in the taste buds of the tongue cover their journey through the cerebral cortex via. thalamus.

Cerebellum lies at the lower back of the head being connected to the brain stem. It is the second largest structure of the brain and is made up of two hemispheres. The cerebellum controls complex motor functions such as walking, balance, posture, and general motor co-ordination including voluntary and involuntary movements.

The human brain is divided into two cerebral hemispheres (left and right), connected by the corpus callosum. Option B is correct. This bilateral structure is fundamental to brain organization. Options A, C, and D are incorrect - humans have exactly two hemispheres, not one, three, or four.

The meninges are three-layered protective membranes (dura mater, arachnoid mater, pia mater) that cover both the brain and spinal cord within the central nervous system. Option A correctly identifies this dual coverage. Options B and C name specific brain regions only, while option D only mentions the spinal cord.

The cerebrum is the largest part of the human brain, comprising about 85% of brain weight and responsible for higher cognitive functions like thinking, reasoning, and voluntary movement. Option A is correct. The cerebellum coordinates balance and movement, the pons regulates breathing and relays signals, and the temporal lobe is just one region within the cerebrum.

Spinal cord is related to the central nervous system

Medulla oblongata controls involuntary actions of the body like heartbeat.

The correct sequence of meninges from inner to outer side is piamater – arachnoid – duramater.

Cerebellum coordinates body movements and maintains posture and balance of the body.

This is the correct option. Pons, cerebellum and medulla form a part of the hindbrain.

The primary circadian clock in mammals is located in the suprachiasmatic nucleus (or nuclei) (SCN), a pair of distinct groups of cells located in the hypothalamus. Destruction of the SCN results in the complete absence of a regular sleep–wake rhythm. The SCN receives information about illumination through the eyes. The retina of the eye contains photoreceptors (rods and cones), which are used for conventional vision. But the retina also contains specialised ganglion cells which are directly photosensitive, and project directly to the SCN where they help in the entrainment of this master circadian clock.

This is the correct answer. Meninges are the three membranes that line the skull and vertebral canal and enclose the brain and spinal cord.

The hypothalamus is a portion of the brain that contains a number of small nuclei and controls body temperature.