Reference To Neuronal Structure Briefly Outline The Processes Of Action Potential Generation And Axonal Conduction And Synaptic And Neuromascular Transmission

Question 1

Explain synaptic transmission

Answer 1

1. Arrival of action potential down the pre synaptic neuron
2. Opens up voltage gated calcium channels
3. Triggers vesicles to move and fuse with nerve membrane
4. Neurotransmitters released from vesicles synthesised by the nerve cell body diffuse across synaptic cleft
5. Acts on specific receptors on post synaptic neurone on its dendrites
6. Sodium is taken up into the post synaptic neurone through the channels and nerve impulse is passed on
7. Any neurotransmitter still in cleft will be reuptaken or inactivated by enzymes

Question 2

What is the neurotransmitter as neuromuscular junctions?

Answer 2

Acetylcholine

Question 3

Explain the interaction between a neuron and a muscle (neuromuscular junction)

Answer 3

1. Nerve impulse arrive at terminal axon
2. Triggers opening of voltage gated calcium channels
3. Vesicles fuse with axon membrane
4. Acetylcholine is released into synapse / synaptic cleft
5. Acetylcholine acts on acetylcholine receptors- these open
6. Sodium enters - if threshold met, action potential is generated in muscle
   Acetylcholine is broken down by acetylcholinesterase