Neurons and synaptic transmission

Question 1

what are the different type of neurone

Answer 1

1) sensory
2) relay
3) motor

Question 2

define a sensory neurone

Answer 2

a type of neurone which carry nerve impulses from sensory receptors to the spinal cord and the brain

Question 3

define a relay neurone

Answer 3

primarily located in the spinal column and allow sensory and motor neurones to communicate with one another

Question 4

define a motor neurone

Answer 4

neurones which form synapses with the bodies effectors, such as muscles or glands, and control their contractions

Question 5

Draw and label a neurone

Answer 5

refer to text book

Question 6

outline the process of a synaptic transmission

Answer 6

1) The action potential reaches the axon terminal
2) this causes the migration of synaptic vesicles to the pre-synaptic membrane
3) the vesicles fuse and release their content- neurotransmitters
4) the content diffuses down the gradient, across the synaptic cleft to the post- synaptic membrane
5) They reach specialised receptors which recognise the neurotransmitter and become activated
6) a new action potential is initiated in the next neurone

Question 7

what is a neurotransmitter

Answer 7

chemical substances which allow the transport of nerve impulses across a synapse from one neurone to the next.

Question 8

what is the difference between excitatory and inhibitory neurotransmitters

Answer 8

1) increases the positive charge within the post-synaptic membrane, increasing the likelihood of it firing a new action potential eg adrenaline
2) increases the negative charge of the post-synaptic membrane, decreasing the likelihood of it firing a new action potential eg serotonin

Question 8

what is the difference between excitatory and inhibitory neurotransmitters

Answer 8

1) increases the positive charge within the post-synaptic membrane, increasing the likelihood of it firing a new action potential eg adrenaline
2) increases the negative charge of the post-synaptic membrane, decreasing the likelihood of it firing a new action potential eg serotonin

Question 9

what is summation

Answer 9

excitatory and inhibitory influences are summed and must reach a certain threshold in order for an action potential
if the net effect is inhibitory it is less likely to fire
if the net effect is excitatory it is more liely to fire