2. Nervous Communication

Receptors

cells which detect stimuli

Effectors

Cells that bring about a response to a stimulus, to produce an effect.

3 types of neurones in the nervous system

• sensory

• relay

• motor

sensory

Transmits electrical impulses from receptors to the central nervous system - the brain and spinal chord

motor

transmits electrical impulses from the CNS to effectors

relay

transmit electrical impulses between sensory and motor neurones

list the nervous system communication chain in order

stimulus → receptors → CNS → Effectors → Response

(relay neurone is within the CNS)

what happens when an electrical impulse reaches the end of a neurone?

chemicals called neurotransmitters take the information across the gap (the synapse) to the next neurone, where another electrical impulse is generated.

simple refelx

a rapid, involuntary response to a stimulus.

• The pathway of communication goes through the spinal cord, but not through conscious parts of the brain, making it happen automatically.

List the pathway of the reflex arc

stimulus → receptors → CNS → Effectors → Response

• (relay neurone in the spinal chord)