Which ion is essential for muscle contraction?

Which of the following is not a characteristic feature of the biceps muscle?

The sensation of fatigue in the muscles after prolonged strenuous physical work is caused by

Red muscle fibres are rich in

What are $HMM$ and $LMM$?

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.