Where are $ATPase$ enzymes located in a muscle fiber?

The mineral element required for blood clotting is also essential for which other process?

Arrange the following steps of muscle contraction in the sequence of events occurring first:
$I.$ Receptor sites on sarcolemma
$II.$ Nerve impulse
$III.$ Release of $Ca^{2+}$
$IV.$ Acetylcholine release
$V.$ Shortening of sarcomere
$VI.$ Synaptic cleft
$VII.$ Spread of impulse over sarcolemma on $T$-tubule
The correct option is:

$A$ motor unit is a

The strongest muscles in the human body are found in the:

In which condition does relaxation occur in muscles?