MICROANATOMY

Detailed explanation-1: -Within the axon terminal are many small vesicles containing a neurotransmitter substance called acetylcholine (ACH). When the action potential reaches the end of the axon, the neurotransmitter is released and diffuses to the muscle cell membrane to combine with receptors there.

Detailed explanation-2: -Acetylcholine is released by the axonal ending, diffuses to the muscle cell, and attaches to the ACh receptors on the sarcolemma. The calcium concentration at the myofilaments increas; the myofilaments slide past one another, and the cell shortens. The muscle cell relaxes and lengthens.

Detailed explanation-3: -Synaptic vesicles (SVs) are small, electron-lucent vesicles that are clustered at presynaptic terminals. They store neurotransmitters and release them by calcium-triggered exocytosis. SVs are made locally at the terminals and are regenerated after exocytosis.

Detailed explanation-4: -Cholinergic neurons release ACh from axon terminals. ACh is synthesized from choline, which is transported into neurons.