Question

At a neuromuscular junction, the muscle fiber membrane folds, forming a

A. motor neuron.
B. neurotransmitter.
C. motor unit.
D. motor end plate.

Answer 1

In a neuromuscular junction, the muscle fiber membrane folds to form the motor end plate, which is key for muscle contraction.

Step-by-step explanation:

At a neuromuscular junction, the muscle fiber membrane folds to form a motor end plate. This structure is crucial in the process of muscle contraction. Situated on the sarcolemma (the muscle fiber membrane) at the neuromuscular junction, the motor end plate contains receptors for the neurotransmitter acetylcholine.

When acetylcholine is released by the synaptic end bulbs of motor neurons, it binds to these receptors, which leads to the depolarization of the sarcolemma, eventually triggering muscle contraction.