Question

multiple choice:
at rest, the tropomyosin molecule is held in place by:
a myosin molecules
b troponin molecules
c actin molecules
d calcium ions
e atp molecules

Explanation:

Troponin molecules bind to tropomyosin and help hold it in place over the active sites of actin when the muscle is at rest. Myosin binds to actin during muscle contraction. Actin is the thin filament. Calcium ions bind to troponin to initiate muscle contraction. ATP is for energy in muscle contraction.

Answer:

B. troponin molecules