Question

Transmission of the nerve impulse across a synapse is accomplished by the what?

Answer 1

Synaptic transmission is a chemical event , involving the release, diffusion, and receptor binding of the neurotransmitter molecules.

Explanation:

The arrival of a nerve impulse at the pre synaptic terminal causes a movement towards a synaptic vesicles. These fuse with the membrane and release neurotransmitters.

The neurotransmitter transmits the nerve impulse to the post synaptic fibres, by diffusing across the synaptic cleft and binding to receptor molecules on the post synaptic membrane.
This results in a series of reactions that open ' channel shaped ' protein molecules. Electrically charged ions then flow through the channels in or out of the neurons.

The synapse along with its neurotransmitters acts as a physiological valve, directing the conduction of nerve impulses in regular circuits and preventing random chaotic stimulation of nerves.