B10- the human nervous system

Question 1

what is a neurone?

Answer 1

Nerve cell; specialised to transmit electrical impulses

Question 2

Sensory neurone

Answer 2

The nerve cell that transmits electrical impulses from receptors in the sense organs to the CNS.

Question 3

motor neurone

Answer 3

The nerve cell that carries electrical impulses from the CNS to effectors

Question 4

Relay neurone

Answer 4

The nerve cell that transmits electrical impulses from sensory neurones to motor neurones

Question 5

stimulus

Answer 5

any change in the environment

Question 6

receptor

Answer 6

Organ that detects a change in the environment

Question 7

Effector

Answer 7

muscles or glands, which bring about response which restore optimum levels

Question 8

central nervous system

Answer 8

the brain and spinal cord

Question 9

reflex

Answer 9

Automatic and rapid response to a stimulus.

Question 10

synapse

Answer 10

A tiny gap between 2 nerves in which the impulse must pass

Question 11

what is the order?

Answer 11

stimulus ->receptor->coordinator->effector->response

Question 12

reflex actions

Answer 12

are automatic and rapid, do not involve the conscious part of the brain

Question 13

give two ways un which a reflex action is different from an action controlled by hormones

Answer 13

a reflex action is rapid as it involves the unconscious part of your brain
reflex action involves electrical impulses whereas hormones involve chemicals

Question 14

explain the reflex arc

Answer 14

1)Receptor in the skin detects a stimulus (the change in temperature).
2)Sensory neuron sends electrical impulses to a relay neuron, which is located in the spinal cord of the CNS. Relay neurons connect sensory neurons to motor neurons.
3)Motor neuron sends electrical impulses to an effector.
4)Effector produces a response (muscle contracts to move the hand away).