Calcium ions initiate sliding of filaments in skeletal muscles by
A)breaking the actin-myosin cross-bridges.
B)binding to the troponin complex,which causes tropomyosin to move and thus expose myosin-binding sites.
C)transmitting action potentials across the neuromuscular junction.
D)spreading action potentials through the T tubules.
E)reestablishing the resting membrane potential following an action potential.

Question

Quizplus · Accepted Answer

When calcium ions bind to the troponin complex, it causes a conformational change that moves tropomyosin out of the way, exposing the myosin-binding sites on actin. This allows for cross-bridge formation between actin and myosin, initiating the sliding of filaments in skeletal muscles.

Calcium Ions Initiate Sliding of Filaments in Skeletal Muscles by