What initiates the excitation-contraction coupling process in muscle fibers?
A) Influx of potassium in the sarcoplasmic reticulum.
B) Relaxation of the muscle fibers.
C) Saturation of myosin with ADP.
D) Release of acetylcholine at the neuromuscular junction.
Answer (1)
The excitation-contraction coupling process in muscle fibers is initiated by the release of acetylcholine at the neuromuscular junction. This neurotransmitter triggers the influx of sodium ions, resulting in an action potential that leads to muscle contraction. Understanding this process is crucial for learning how muscles function during physical activity. ;
