Define sliding filament theory of muscle contraction.

According to the sliding filament theory of muscle contraction,

During muscle contraction

Go through the following statements During muscle contraction, the width of A-band remains constant while I-band shortens. During muscle contraction, the Ca^(2+) released from the SR bind to the troponin component of thin filament The process of muscle contraction is faster in smooth muscle as they have a well developed sarcoplasmic reticulum. The red muscle fibres have abundant mitochondria, low glycogen and poorly formed sarcoplasmic reticulum.

Cardiac muscles contract

Which ion is essential for muscle contraction ?

Sliding filament theory can be best explained as