MICROANATOMY

Detailed explanation-1: -The acetylcholine binds to the nicotinic receptors concentrated on the motor end plate, a specialized area of the muscle fibre’s post-synaptic membrane. This binding causes the nicotinic receptor channels to open and let sodium ions enter the muscle fibre.

Detailed explanation-2: -The ACh then binds to its receptors (ligand-gated cation channels) present on the surface of the sarcolemma (membrane of the post-synaptic muscle cell). This binding causes the opening of ligand-gated sodium ion (cation) channels which results in the influx of sodium ions into the muscle cell.

Detailed explanation-3: -The “motor end plate” part of the sarcolemma contains acetylcholine (ACh) receptors.

Detailed explanation-4: -Acetylcholine binds to receptors on the sarcolemma. Sodium, potassium, and other cations begin to flow across the cell membrane, generating an action potential within the muscle fiber. The muscle contracts.