In the resting state,a subunit of troponin masks the active binding sites for .......... on the .......... filaments.

$A$ collagenous connective tissue layer holds the muscle bundles together.

Muscles are red because of the presence of

Actin and myosin proteins are related with

$ATPase$ enzyme needed for muscle contraction is located in

During muscular contraction,which of the following events occur?
$(a)$ $'H'$ zone disappears
$(b)$ $'A'$ band widens
$(c)$ $'I'$ band reduces in width
$(d)$ Myosin hydrolyzes $ATP$,releasing the $ADP$ and $\Pi$
$(e)$ $Z$-lines attached to actins are pulled inwards
Choose the correct answer from the options given below.