The Process Of Synaptic Transmission

Question 1

Two types of neural communication - electrical communication

Answer 1

When a neuron is resting the cell has a negative charge. When activated by a stimulus, the inside of the cell becomes positively charged for a split second, causing the action potential (electrical impulse that travels down the axon towards the end of the neuron)

Question 2

Two types of neural communication - chemical communication

Answer 2

When the action potential reaches the end of the neuron it has nowhere to go as each neuron is separated by a tiny gap called the synapse. The only way messages can be sent through the synapse is by chemical transmission through the use of neurotransmitters. (Synaptic transmission)

Question 3

Define neurotransmitters

Answer 3

Chemical messengers found at the synapse

Question 4

Stages of Synaptic Transmission

Question 5

What is excitation ( 4 points)

Answer 5

A neurrotransmitter eg adrenaline causes the postsynaptic neuron to become more positively charged. This lowers the threshold (depolarisation) and therefore increases the firing rate of the action potential in the post synapse.

Question 6

What is inhibition (4 points)

Answer 6

A neurotransmitters eg Serotonin causes the post synaptic neuron to become more negatively charged. This highers the threshold (hyperpolarisation) and therefore decreases the firing rate of the action potential in the post synapse.

Question 7

What is summation

Answer 7

A cell can receive both excitatory and inhibitory neurotransmitters at the same time. The synaptic firing is determined by adding up the excitatory and inhibitory input

More inhibitory - electrical impulse halted
More excitatory - electrical impulse would continue

Question 8

Spatial Summation

Answer 8

Excitatory potentials from many neurons trigger threshold point

Question 9

Temporal Summation

Answer 9

Mandy excitatory potentials from one neuron triggers threshold point