The "myosin binding site" is present on:

Who put forward the sliding filament theory?

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.

Titan filament connects

The immediate source of energy for muscle contraction is ...... .

The functional unit of the contractile system in the striped muscle is