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 nerve 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 massages travel through the nerves Q and S?

Answer

(a) P is a receptor; Eyes, Ears, Nose, Tongue and skin (b) Sensory nerves (c) Effector; Muscles and Glands (d) Motor nerves (e) In the form of electrical impulses