P is a cell (or group of cells) in the human body which is sensitive to a particular type of stimulus and conveys the messages to CNS through nerves Q. On the other hand, R is a part of the human body which can respond to a stimulus according to the instructions sent from the CNS through nerves S.
(a) What is P? Name five organs which contain cells (or group of cells) like P.
(b) Name the nerves Q.
(c) What is R? Give two examples of R.
(d) Name nerves S.
(e) How do messages travel through the nerves Q and S?

Open in App

Solution

(a) P is a receptor. The five organs which contain receptors are: eyes, ears, nose, tongue and skin.

(b) Q represents sensory nerves. Sensory nerves bring impulses from sensory organs to the CNS.

(c) R is an effector organ. Effectors are part of the human body which can respond to a stimulus according to the instructions sent from the CNS though the motor nerves. Two examples of effector organs are the muscles and glands.

(d) S represents motor nerves. Motor nerves carry impulse from the CNS to the effector organs like the muscles or glands.

(e) Messages travel in the form of electrical impulses or nerve impulses through sensory nerves (Q) and motor nerves (S).

Suggest Corrections

Similar questions

	List I		List II
A	Cyton	p	The body of the nerve cell that contains the organelles.
B	Dendrite	q	Receives the stimuli sent from another nerve or the outside environment.
C	Axon	r	A fatty substance that covers the axon of the nerve cell and speeds.
D	Myelin sheath	s	The long, thin section of the nerve cell where the impulse is transmitted across.

(a) Why are nerve cells long and have branches ?
(b) What is the other name of a nerve cell ?

Join BYJU'S Learning Program