Neurons and synaptic transmission

Question 1

What are neurons?

Answer 1

Cells specialised to carry neural information throughout the body

Question 2

What are the 3 types of neuron?

Answer 2

Motor, sensory and relay

Question 3

What is the distinguishing factor of a relay neuron?

Answer 3

It is not myelinated

Question 4

What is the distinguishing factor of a sensory neuron?

Answer 4

Its cell body is off to the side

Question 5

What is the distinguishing factor of a motor neuron?

Answer 5

It is connected to a muscle

Question 6

What do sensory neurons do?

Answer 6

Carry nerve impulses from sensory receptors to the CNS

Question 7

What do relay neurons do?

Answer 7

Allow sensory and motor neurons to communicate

Question 8

What do relay neurons coordinate?

Answer 8

A response

Question 9

What do motor neurons do?

Answer 9

Conduct nerve impulses from the CNS to effectors

Question 10

Give 2 examples of effectors.

Answer 10

Muscles and glands

Question 11

What is the myelin sheath?

Answer 11

An insulating layer around the axon

Question 12

What is synaptic transmission?

Answer 12

The process by which a nerve impulse passes from the pre-synaptic neuron to the post-synaptic neuron

Question 13

What is a synapse?

Answer 13

The gap between neurons

Question 14

When a nerve impulse arrives at a presynaptic neuron, what does it trigger?

Answer 14

An influx of calcium ions

Question 15

What does the influx of calcium ions stimulate during synaptic transmission?

Answer 15

Vesicles to move to the presynaptic membrane

Question 16

What do vesicles contain in presynaptic neurons?

Answer 16

Neurotransmitters

Question 17

What happens when vesicles bind to the presynaptic membrane?

Answer 17

The neurotransmitters diffuse across the synapse

Question 18

What do neurotransmitters bind to on the postsynaptic membrane?

Answer 18

Receptor sites

Question 19

What are neurotransmitters?

Answer 19

Chemical messengers that carry signals across a synapse

Question 20

What are the 2 types of neurotransmitters?

Answer 20

Excitatory and Inhibitory

Question 21

What do excitatory neurotransmitters do?

Answer 21

Increase the likelihood of a neuron firing

Question 22

Give an example of an excitatory neurotransmitter.

Answer 22

Dopamine

Question 23

What do inhibitory neurotransmitters do?

Answer 23

Decrease the likelihood of a neuron firing

Question 24

Give an example of an inhibitory neurotransmitter.

Answer 24

Serotonin

Question 25

What is an EPSP?

Answer 25

A postsynaptic potential that makes the postsynaptic neuron more likely to fire an action potential

Question 26

What is an IPSP?

Answer 26

A postsynaptic potential that makes the postsynaptic neuron less likely to fire an action potential

Question 27

What is summation?

Answer 27

The net result of IPSPs and EPSPs firing at the same time

Question 28

What are the 2 types of summation?

Answer 28

Spatial and temporal

Question 29

What is spatial summation?

Answer 29

When nerve impulses are generated in the postsynaptic neuron from multiple presynaptic neurons

Question 30

What is temporal summation?

Answer 30

When a large number of nerve impulses are generated at the postsynaptic neuron due to rapid firing of the same presynaptic neuron