The triceps muscle connects the ulna with which of the following bones?

In which of the following,growth is possible through increase in volume?

Which bands contain only actin and only myosin filaments,respectively?

Given below are two statements:
$Statement-I$: Plasma creatinine is produced during catabolism of creatinine phosphate in skeletal muscle contraction.
$Statement-II$: Creatinine phosphate provides a ready source of high-energy phosphate.
In the light of the above two statements, choose the most appropriate answer from the options given below.

Thigh muscles get tired but not the muscles of the ventricle of heart because

The given figure represents the cross-bridge cycle in skeletal muscle. What does step $B$ in the figure represent?