MICROANATOMY

Detailed explanation-1: -Myosin forms filaments in an antiparallel fashion at the center of the thick filament, while myosin forms filaments in a parallel way in the rest of the thick filament. Consequently, a bipolar thick filament is formed, leaving a central bare zone in the middle.

Detailed explanation-2: -An individual sarcomere contains many parallel actin (thin) and myosin (thick) filaments.

Detailed explanation-3: -Thick filaments are composed of dimers of a remarkable force-generating protein called myosin. Allmyosin molecules have helical tails and globular head groups that hydrolyze ATP and act as motors to move along an actin filament.

Detailed explanation-4: -The thin filament of contractile muscle contains actin, myosin, and troponin, a complex of three proteins.

Detailed explanation-5: -The I bands contain only thin (actin) filaments, whereas the A bands contain thick (myosin) filaments. The myosin and actin filaments overlap in peripheral regions of the A band, whereas a middle region (called the H zone) contains only myosin.