Nervous System Physiology

The hindbrain is the lowermost or rearmost region of the brain that bridges the brain with the spinal cord and includes the medulla oblongata, pons and cerebellum. It is also called the rhombencephalon.  

Arbor vitae which is the largest white matter present in the center of the cerebellum. It is so called for its branched, tree-like appearance. It is important in the coordination of the arms, legs and any actions requiring hand-eye coordination. Hence, the correct answer is option A.

The arbor vitae is the cerebellar white matter, so called for its branched, tree-like appearance. It resembles a fern and is present in both cerebellar hemispheres. It brings sensory and motor information to and from the cerebellum. It is located deep in the cerebellum. So, the correct answer is option B.

Cerebrum is the largest part of the brain and well developed in humans. It plans, thinks, judges, and organised speech and information. It consists of two hemispheres, left and right connected by corpus callosum. 

The lateral ventricles are part of the ventricular system of the brain. Both cerebral hemispheres contain a lateral ventricle. The lateral ventricles are the largest of the ventricles.

The hypothalamus is located below the thalamus, just above the brainstem. It forms the ventral part of the diencephalon. 

The osmoreceptors are specialised cells in the hypothalamus, which respond to changes in extracellular tonicity. $Na^+$ accounts for 92% of ECF tonicity, these receptors function as monitors of ECF [$Na^+$]. These receptors are called as osmo-sodium receptors. The osmoreceptors effectively respond to the ECF [$Na^+$] and this is also the factor, which effectively controls the distribution of water between intracellular and extracellular fluid.

One of the major functions of the hypothalamus is to maintain homeostasis, to keep the human body in a stable, constant condition. The hypothalamus responds to a variety of signals from the internal and external environment including body temperature, hunger, feelings of being full up after eating, blood pressure and levels of hormones in the circulation. 

Broca's area is a region in the frontal lobe of the left hemisphere in the cerebral cortex with functions linked to speech production. Broca's area is located in the lower portion of the left frontal lobe.

The temporal lobe controls hearing. The temporal lobe is located below the lateral fissure on both hemispheres of the brain.

Emotion involves two parts of the nervous system - the limbic system and the autonomic nervous system. The limbic system is a complex set of structures, that lies on both sides of the thalamus, just under the cerebrum. It includes the hypothalamus, the hippocampus, the amygdala. The hypothalamus feeds information into the amygdala. The hypothalamus acts as a regulator of emotion, controlling levels of sexual desire, pleasure, aggression and anger.

The occipital lobe is the visual processing center of the mammalian brain containing most of the anatomical region of the visual cortex. The occipital lobes are part of the forebrain. A significant functional aspect of the occipital lobe is that it contains the primary visual cortex. The optic lobes are especially prominent in fish and birds.

As we move from fish to mammals, there is an observable increase in the brain size relative to the body size. This progressive increase is mainly observed in the form of an increase in the size of cerebral hemispheres or the cerebellum. So, the correct answer is 'Cerebrum'.

The hypothalamus acts as the primary control center for the endocrine system by receiving signals about body conditions and regulating the pituitary gland. It links the nervous and endocrine systems.

The cerebellum is the part of the brain responsible for coordinating voluntary movements, posture, and maintaining the body's balance and equilibrium. The cerebrum controls higher cognitive functions, while olfactory lobes are responsible for the sense of smell.