Synaptic Transmission

Question 1

Define Synaptic Transmission

Answer 1

The process by which neighbouring neurons communicate with each other by sending chemical messages across a synapse

Question 2

Explain Synaptic Transmission

Answer 2

1. When the electrical impulse reaches the end of the neuron (pre-synaptic terminal) it triggers the release of neurotransmitters from tiny sacs called synaptic vesicles
2. Once the neurotransmitters have diffused across the synapse, they are taken up by postsynaptic receptor sites (dendrites of the next neuron)
3. The chemical message is then converted back into an electrical impulse and the process continues in this neuron

Question 3

Define Neurotransmitter

Answer 3

Chemicals that are produced by the neuron and diffuse across the synapse to the next neuron
Have specialist functions
Carries the chemical message across the synapse

Question 4

Define Excitation

Answer 4

Caused by Adrenaline
Increases the postsynaptic neuron’s positive charge making it more likely to fire

Question 5

Define Inhibition

Answer 5

Caused by Serotonin
Cause the postsynaptic neuron to become more negatively charged and less likely to fire

Question 6

What is Summation

Answer 6

Action potential of the postsynaptic neuron is only triggered if the sum of the excitatory and inhibitory signals at any one time reaches the threshold