Question

Regarding the events in the chemical synapse of a vertebrate neuromuscular junction. Which series is in the correct order?

a) AP in axon terminal motor neuron, voltage calcium channels open, release ACh into cleft, receptor on presynaptic membrane bind ACh, Na+ and K+ channels open post synaptic cell
b) AP in axon terminal motor neuron, voltage calcium channels open, release ACh into cleft, receptor on postsynaptic membrane bind ACh, Na+ and K+ channels open postsynaptic cell
c) Voltage calcium channels open, AP in motor neuron, ACh release, receptor on postsynaptic membrane bind ACh, Na+ and K+ channels open postsynaptic cell
d) AP in motor neuron, Na+ and K+ flow in post synaptic cell, calcium release, ACh channels open, AP in post synaptic cell

Answer 1

The correct order of events in the chemical synapse of a vertebrate neuromuscular junction is: AP in axon terminal motor neuron, voltage calcium channels open, release ACh into cleft, receptor on postsynaptic membrane bind ACh, Na+ and K+ channels open postsynaptic cell. First, an action potential is generated in the axon terminal of a motor neuron.

Step-by-step explanation:

The correct order of events in the chemical synapse of a vertebrate neuromuscular junction is:

Receptor on postsynaptic membrane bind ACh

Postsynaptic cell depolarizes

First, an action potential is generated in the axon terminal of a motor neuron.

This causes voltage-gated calcium channels to open, leading to an influx of calcium ions.

The calcium ions then trigger the release of the neurotransmitter acetylcholine (ACh) into the synaptic cleft. ACh binds to receptors on the postsynaptic membrane of the motor end plate, leading to the opening of sodium (Na+) and potassium (K+) channels in the postsynaptic cell.

This results in depolarization of the postsynaptic cell, which propagates as an action potential.