Biology
State the functions of the following:
(a) Association neuron
(b) Myelin sheath
(c) Medullary sheath
(d) Cerebrospinal fluid
Nervous System
102 Likes
Answer
(a) Association neuron — Association neurons carry impulses from the motor neuron to the Central Nervous System (CNS) or a nerve cell found entirely within the central nervous system. It acts as a connecting neuron and interconnects the sensory and motor neurons.
(b) Myelin sheath — It acts like an insulation and prevents mixing of impulses in the adjacent axons.
(c) Medullary sheath — It provides insulation and prevents mixing of impulses in the adjacent axons.
(d) Cerebrospinal fluid — It acts like a cushion and protects the brain from shocks.
Answered By
72 Likes
Related Questions
State whether the following statements are true (T) or false (F).
(a) The main component of the white matter of the brain is perikaryon.
(b) The arachnoid layer fits closely inside the pia mater.
(c) A double chain of ganglia, one on each side of the nerve cord belongs to the spinal cord.
(d) Dura mater is the outermost layer of the meninges.
State whether the following are simple reflexes, conditioned reflexes or neither of the two.
(i) Sneezing……………………
(ii) Blushing……………………
(iii) Contraction of eye pupil………………..
(iv) Lifting up a book……………………
(v) Knitting without looking…………………
(vi) Sudden application of brakes of the cycle on sighting an obstacle in front……………….
Rearrange the following in correct sequence pertaining to what is given within brackets at the end.
(a) Effector — Sensory neuron — Receptor — Motor neuron — Stimulus — Central nervous system — Response (Reflex arc)
(b) Repolarization — Depolarization — Resting (polarsied) (during conduction of nerve impulse through a nerve fibre)
(c) Axon endings — Dendrites — Axon — Perikaryon — Dendron (Neuron structure)
(d) Diencephalon — Cerebellum — Medulla oblongata — Pons — Cerebrum — mid brain (sequence of parts of human brain).
Name three types of neurons.