The contraction of skeletal muscles is based on
A) actin filaments coiling up to become shorter.
B) myosin filaments coiling up to become shorter.
C) actin and myosin filaments both coiling up to become shorter.
D) actin cross-bridges binding to myosin and transitioning from a high-energy to a low-energy state.
E) myosin cross-bridges binding to actin and transitioning from a high-energy to a low-energy state.

Question

Quizplus · Accepted Answer

The contraction of skeletal muscles is based on myosin cross-bridges binding to actin and transitioning from a high-energy to a low-energy state. This process is called the sliding filament theory, in which myosin filaments attach to actin filaments and pull them closer together, shortening the muscle fiber and causing a contraction. Actin filaments themselves do not coil up to become shorter during muscle contraction.

The Contraction of Skeletal Muscles Is Based on