reflex actions.

Question 1

how are reflex actions carried out and why?

Answer 1

automatically so they can protect the body.

Question 2

what is the process of the message being sent in a scenario where a reflex action is used?

Answer 2

pain stimulus is detected by receptors.
impulses from receptor pass along sensory neurones to CNS.
an impulse then passes through the relay neurone.
motor neurone carries impulse to the effector.
effector ( usually a muscle.) responds. eg: withdraw a limb away from source of pain.

Question 3

what is a synapse?

Answer 3

junction between 2 neurons.
a small gap exists because the 2 neurons, which an electrical impulse cannot pass across.

Question 4

how do synapses work: stage 1.

Answer 4

electrical signals travel down sensory neurones.

Question 5

how do synapses work: stage 2.

Answer 5

neurotransmitters releases into synapse.

Question 6

how do synapses work: stage 3.

Answer 6

diffuses across synapse.

Question 7

how do synapses work: stage 4.

Answer 7

joins/ binds with receptors.

Question 8

how do synapses work: stage 5.

Answer 8

causes electrical signals to generate in relay neuron.