Neurons and synaptic information part two

Question 1

explain the process of synaptic transmission

Answer 1

• an electrical impulse passes down information along an axon - action potential
• once the action potential reaches the end of an axon it needs to be transferred to another neuron or tissue
• it must cross over the synaptic gap between the presynaptic neuron and the postsynaptic neuron
• at the end of a neuron (axon terminal) there are vesicles which contain neurotransmitters
• when the action potential reaches these synaptic vesicles they release their contents of neurotransmitters through exocytosis
• the neurotransmitters carry the signal across the synaptic gap
• they bond to receptor sites on the postsynaptic cell
• once activated they produce excitatory or inhibitory effects
• the neurotransmitters can either be broken
• this is synaptic transmission

Question 2

What are exictatory neurotransmitters?

Answer 2

Excitatory neurotransmitters are the nervous systems ‘on switches’ (e.g. noradrenaline) they make the post-synaptic cell more likely to fire.

Question 3

what are inhibitory neurotransmitters?

Answer 3

inhibitory neurotransmitters are the nervous systems ‘off switches’ (e.g. GABA) make the post-synaptic cell less likely to fire.

Question 4

what is EPSP?

Answer 4

excitatory post-synaptic potential
if an excitatory neurotransmitter like noradrenaline binds to the post synaptic receptor it will cause an electrical charge in the cell membrane which results in an EPSP

Question 5

What is IPSP

Answer 5

inhibitory post synaptic potential
if an inhibitory neurotransmitter such as GABA binds to the post synaptic receptors it will result in IPSP which makes the post synaptic cell less likely to fire.

Question 6

what is summation?

Answer 6

the net result of the likelihood of a cell firing which is determined by the the adding up of the excitatory and the inhibitory synaptic input (a nerve cell can receive both EPSP and IPSP)