neurons and synaptic transmission ao1

Question 1

What kind of transmission occurs within a neuron

Answer 1

electrical transmission

Question 2

what travels down a neuron and how is it stimulated

Answer 2

• action potential
• in its resting state cell is -ve charged
• stimulus leads to +ve charge
  = AP
  = electrical impulse

Question 3

5 parts of neuron

Answer 3

dendrites
cell body
axon
myelinated sheath
axon terminal

Question 4

3 types of neuron

Answer 4

motor neuron
relay neuron
sensory neuron

Question 5

sensory neurons carry info from ____
to ____

Answer 5

sensory neurons carry information from PNS to CNS

Question 6

Motor neurons are found in the ___

Answer 6

CNS

Question 7

Motor neurons connect the ____ to _________ such as ________ or ______

Answer 7

Motor neurons connect the CNS to effectors like muscles or glands

Question 8

How do motor neurons work

Answer 8

when stimulated they release neurotransmitters that bind to receptors on muscles to trigger a response which leads to movement

Question 9

Relay neurons are found between

Answer 9

Sensory neurone input and motor neuron response
Mainly found in brain and spinal cord

Question 10

Relay neurons allow communication between ….

Answer 10

Sensory and motor neurons

Question 11

Describe struc of neurons

Answer 11

Dendrites are branch like structures that receive nerve impulses from neighbouring neurons or sensory receptors like skin
Carrying that info to the cell body
Contains a nucleus thag has genetic material of the cell
Axon carries impulses in the form of AP away from cell body to the axon terminal
Axon is insulated by myelin sheath protecting axon and speeding up electrical transmission of the impulse
Nodes of ranvier which a gaps also help speed up transmission by forcing impulse to jump along the gaps
Axon terminals communicate w the next neuron across the synapse

Question 12

Gap between neurons

Answer 12

Synapse

Question 13

Information within neurons is transmitted _______ whilst info between neurons is transmitted ________

Answer 13

Information within neurons is transmitted electricallly whilst info between neurons is transmitted chemically

Question 14

Describe synaptic transmission
Hint: there are 6 steps

Answer 14

1) impulse arrives at presynaptic neuron
2) neurotransmitters rel from vesicles
3) neurotransmitters diffuse across synapse
4) bind to receptor sites on post synaptic neuron
5) chemical message converted back to electrical impulse
6) neurotransmitters broken down and reabsorbed into the presynaptic neuron

Question 15

Why is synaptic transmission unidirectional

Answer 15

Rel from pre and bind to receptors on post
No receptors on pre , no vesicles w neurotransmitters in them in post

Question 16

What is a neurotransmitter

Answer 16

Chemicals that diffuse across synapse to next neurone in the brain
Each has its own specific function

Question 17

2 effects that neurotransmitters have on neurons

Answer 17

Excitation or inhibition

Question 18

What is excitation and give example

Answer 18

Neuron more positive
More likely to fire
Adrenaline

Question 19

What is inhibition and give an example

Answer 19

Increased neg charge
Less likely to ire
Eg serotonin

Question 20

What is summation

Answer 20

Excitatory and inhibitory effects are summed so if net effect is excitatory then the post neuron is more likely to fire and vice versa