Synapses

Question 1

between what 3 cells can chemical synapses occur

Answer 1

between neurons and ..
neurons
muscle cells
glands

Question 2

describe the events at a chemical synapse

Answer 2

1 - AP travels down membrane depolarising it until it reaches voltage gated Ca channels
2 - AP stimulates channels to open due to voltage change allowing influx of CA+ into cell
3 - Ca ions stimulate vesicles to release neurotransmitters into the synaptic cleft
4 - neurotransmitters bind to receptors on the post synaptic cell resulting in changes

Question 3

what are 3 methods of neurotransmitter removal

Answer 3

re -uptake by pre synaptic neuron, often recycled and used again
diffusion - passive process, cant be used in situations with high frequency AP
enzymatic destruction - enzymes breakdown neurotransmitters

Question 4

excitatory neurotransmitters

Answer 4

transmitter causes depolarisation increasing cell activity

Question 5

inhibitory neurotransmitters

Answer 5

transmitter causes hyperpolarisation which decreases cell activity

Question 6

summation

Answer 6

post synaptic membrane potentials often add up together in an attempt to reach threshold

Question 7

convergence

Answer 7

each neuron receives inputs from many other cells

Question 8

divergence

Answer 8

each neuron synapses with many other cells

Question 9

what neurotransmitter is used at neuromuscular junctions

Answer 9

acetyl choline