The mechanism of muscle contraction is best explained by:

$A-$ Actin filaments occur in two forms: the monomeric $G$-actin and the polymeric $F$-actin.
$R-$ Tropomyosin is a rod-shaped fibrous protein. Tropomyosin forms two helical strands,which are wrapped around the $F$-actin filaments.

In the resting state of muscles, where is calcium stored?

Muscle fatigue occurs due to the accumulation of . . . . . . .

Myosin head separates from actin when:

Who put forward the sliding filament theory?