The structure labeled

"Troponin" is shown situated directly on the myosin heads,

facilitating their attachment to actin.

“H zone" represents the region of

the sarcomere containing only thick filaments and the M line

Thick filaments consist of bundled myosin

molecules where the "Heads" project outwards, and these heads are

connected to the myosin "Tail" via a "Flexible hinge

region".

The thin filaments are shown to be

composed solely of actin subunits.

Each individual myosin molecule

illustrated possesses distinct "Actin-binding sites" and an

"ATP-binding site", both located on the heads.

The

"I band" is depicted as a region containing the Z line and portions

of the thick filaments extending from Z line.