Definitions

Question 1

CNS

Answer 1

central nervous system: the brain and spinal chord

Question 2

PNS

Answer 2

peripheral nervous system: all nerves in the body

Question 3

define nerve

Answer 3

a bundle of neurones

Question 4

define voluntary action

Answer 4

it is a response made consciously to carry out a specific action and involves the brain

Question 5

define involuntary action

Answer 5

an involuntary response does not involve the brain as the coordinator of the reaction and you are not aware you have completed it until after you have

Question 6

define receptors

Answer 6

a group of specialised cells that detect a change in the environment and stimulate electrical impulses in response

Question 7

define sense organs

Answer 7

these organs contain groups of receptor cells that respond to specific stimuli

Question 8

define sensitivity

Answer 8

it is the ability to sense and detect a stimuli in the internal or external environment and make an appropriate response

Question 9

define a hormone

Answer 9

a hormone is a chemical substance produced by a gland and carried by the blood which altars the activity of one or more specific target organs