Synaptic transmission

Question 1

Synaptic transmission

Answer 1

Process for transmitting messages from 1 neuron to the next

Electrical impulse from the neuron is carried by chemicals through the synapse to the next neuron

Question 2

Process of synaptic transmission

Answer 2

Electrical impulse travels down axon in the pre-synaptic neuron,

Vesicles at end of axon contain neurotransmitters, when the electrical impulse reaches the vesicle, it causes them to release their contents across the synapse

Neurotransmitters then diffuse across the synapse

In the adjacent neuron, neurotransmitters bind to the receptors and are then converted back into electrical impulses to travel down the next neuron

Question 3

Excitatory neurotransmitter

Answer 3

Nervous systems ‘on switches’ and they increase the likelihood of the post-synaptic neuron firing

Question 4

Inhibitory neurotransmitters

Answer 4

Nervous system ‘off switches’ and they decrease the likelihood of the neuron firing

Question 5

Summation

Answer 5

A neuron firing depends on summation

If the sum of the neurotransmitters entering the post-synaptic neuron are excitatory the neuron will fire

If the sum of the neurotransmitters entering are inhibitory, the neuron will be less likely to fire

Question 6

Dendrites

Answer 6

Carry nerve impulses from neighbouring neurons towards cell body

Question 7

Cell body

Answer 7

Includes a nucleus

Question 8

Nucleus

Answer 8

Inside cell body, contains genetic material

Question 9

Axon

Answer 9

Carries electrical impulse away from cell body down length of neuron

Question 10

Myelin sheath

Answer 10

Fatty layer that protects and insulates axon

Question 11

Nodes of ranvier

Answer 11

Gaps in axon that speed up transmission of impulse

Question 12

Axon terminal

Answer 12

Where nerve impulses pass from one nerve to another by crossing synaptic gap