MICROANATOMY

Detailed explanation-1: -This central region of the A band looks slightly lighter than the rest of the A band and is called the H zone. The middle of the H zone has a vertical line called the M line, at which accessory proteins hold together thick filaments.

Detailed explanation-2: -Each sarcomere has a central A band made of thick myosin filaments and two half I bands made of thin actin filaments on either side of the thick filaments leaving the central part of the thick filaments. This central part of thick filament, not overlapped by thin filament is called H zone.

Detailed explanation-3: -The dark bands are called A bands while the light regions are termed I bands . The A bands are themselves striped, consisting of a lighter central band called the H zone (or AH zone) flanked by two darker regions (AI zones). At the centre of the H zone is a thin dark line, the M line (or M disc).

Detailed explanation-4: -H-band is the zone of the thick filaments that has no actin. Within the H-zone is a thin M-line (from the German “mittel” meaning middle), appears in the middle of the sarcomere formed of cross-connecting elements of the cytoskeleton.

Detailed explanation-5: -Hensen’s disc is the other name of H-band in the sarcomere. It is a zone across the center of the sarcomeres of skeletal muscle cells. Within the A-band is a paler region called the H-zone.