What is a reflex arc? And how many parts does it consists of?

1.	What is a reflex arc? And how many parts does it consists of?
Answer» The path travelled by an impulse in a reflex action is called the reflex arc. It consists of five parts: (i) A receptor or skin, the neurons of which start a sensory impulse. (ii) An afferent nerve, which brings sensory impulse from the receptor to the central nervous system. (iii) The neurons present in the spinal cord change the sensory impulse into the motor impulse. (iv) An efferent nerve, which carries the motor impulses from the spinal cord to the specific effectors like muscles fibres or gland cells. (v) An effector, where impulse terminates and response is given.

Answer»

The path travelled by an impulse in a reflex action is called the reflex arc.

It consists of five parts:

(i) A receptor or skin, the neurons of which start a sensory impulse.

(ii) An afferent nerve, which brings sensory impulse from the receptor to the central nervous system.

(iii) The neurons present in the spinal cord change the sensory impulse into the motor impulse.

(iv) An efferent nerve, which carries the motor impulses from the spinal cord to the specific effectors like muscles fibres or gland cells.

(v) An effector, where impulse terminates and response is given.

Discussion