Differentiate between striated muscle fibers and visceral muscle fibers.

Identify the bands $P, Q,$ and $R$ in the given diagram.
$\quad\quad\quad P \quad\quad\quad Q\quad\quad\quad R$

Titan filament connects

In a resting state,the central part of the thick filaments not overlapped by thin filaments is called the .....

Which ion is essential for muscle contraction?

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.