Synapse

Question 1

Define synapse

Answer 1

Where one neurone connects with another/ and effector

Question 2

Name the parts of the synapse and the neighbouring neurones

5

Answer 2

Presynaptic neurone
Postsynaptic neurone 
Synaptic Knob
Synaptic Cleft
Synaptic Vesicle

Question 3

Name the 2 features of a synapse

Answer 3

Unidirectional

Summation

Question 4

Describe unidirectional in relation to a synapse

Answer 4

Always presynaptic 2 postsynaptic neurone

Question 5

Name the two types of summation

Answer 5

Spatial and Temporal Summation

Question 6

Describe Spatial Summation

Answer 6

Multiple presynaptic neurones release neurotransmitters to exceed the threshold value

Question 7

Describe Temporal Summation

Answer 7

Single presynaptic neurone release lots over a short period

Question 8

Name the two functions of the synapse

Answer 8

Allow single impulse in one neurone to initiate new impulses in multiple neurones
No of impulses combine at the synapse

Question 9

Describe how the inhibition synapse works

Answer 9

Presynaptic release neurone transmitter the binds to the Cl- protein channel on the postsynaptic neurone
This opens the channels so Cl-move into neurone via facilitated diffusion
Binding of neurotransmitter causes opening of K+ protein channels so K+ moves out of the synapse into the channel.
This makes the inside more negative and outside moire positive
= Hyperpolaristion

Question 10

Why does the inhibitory synapse inhibit?

Answer 10

Less likely to create AP as a large influx of Na+ is needed

Question 11

Name the synapse that Acetylcholine binds to

Answer 11

Cholinergic Synapse

Question 12

Describe what an action potential to be produced

Answer 12

AP arrives at end of the presynaptic neurone which opens the Ca2+ channels so Ca2+ enter via facilitated diffusion
The influx of Ca2+ in the presynaptic neurone causes the synaptic vesicle to fuse with the presynaptic membrane and release acetylcholine into the synaptic cleft
Acetylcholine diffuses quickly bc diffusion pathway is short
Then binds to the receptor site on Na+ channel in a membrane of the postsynaptic neurone. This opens the channel and so Na+ enter along with their con. gradient.
New AP generated by the influx of Na+ in past

Question 13

What occurs to the Acetylcholine after binding to the Na+ channel?
And why?

Answer 13

Acetylcholinease hydrolyse it into acetyl and choline which diffuses back into the presynaptic neurone where ATP recombines acetylcholine and stores it in a vesicle
This also prevents a continual generated ATP