When Acetylcholine Binds to Receptors at the Motor End Plate

Question

When acetylcholine binds to receptors at the motor end plate, the sarcolemma becomes
A) more permeable to sodium ions.
B) less permeable to sodium ions.
C) more permeable to calcium ions.
D) less permeable to potassium ions.
E) less permeable to potassium and sodium ions.

Accepted Answer

Acetylcholine binding to receptors at the motor end plate causes an increase in the permeability of the sarcolemma to sodium ions, which results in depolarization of the membrane potential and initiation of muscle contraction. It does not directly affect calcium or potassium ions.