Control and Co-ordination — BIOLOGY STD 12 Science — Question

(A) Functions of cerebrum:

1. The cerebrum controls the voluntary activities.
2. The cerebrum perceives various sensory stimuli received through vision, taste, smell, sound, touch, speech, etc.
3. It is the centre of memory, will-power, intelligence, reasoning and learning.
4. The cerebrum is the centre for emotions, thoughts and feelings, pain, pleasure, fear, fatigue, pressure, temperature, etc.
5. It is also the centre for micturition, defecation, weeping, laughing, etc

(B) Function of olfactory lobes: Sensation of smell.

(C) Functions of diencephalon:

1. Diencephalon acts as a relay centre for motor and sensory impulses between spinal cord, brainstem and various areas of cerebral cortex.
2. Diencephalon consists of epithalamus, thalami and hypothalamus. Therefore it acts as a centre for homeostasis and higher centre of autonomous nervous system.
3. Hypothalamic nuclei secrete neurohormones which influence the pituitary gland.
4. Diencephalon regulates heartbeats, blood pressure and water balance.
5. Anterior choroid plexus which is located in the diencephalon secretes cerebrospinal fluid.
6. Hypothalmic regions control many involuntary functions such as hunger, thirst, thermo-regulation, fear, anger, sleep, sexual desire, etc.