NEET2013ZoologyLocomotion and MovementActual
The H-zone in the skeletal muscle fibre is due to
Options
- Athe absence of myofibrils in the central portion of A-band
- Bthe central gap between myosin filaments in the A-band
- Cthe central gap between actin filaments extending through myosin filaments in the A-band
- Dextension of myosin filaments in the central portion of the A-band
Correct answer
C. the central gap between actin filaments extending through myosin filaments in the A-band
Step-by-step solution
H -zone in skeletal muscle is the central gap between actin filaments extending through myosin filaments in the A-band. Alternate arrangement of dark and light bands gives the striated appearance to a skeletal muscle. At the centre of A-band, a comparatively less dark zone called H -zone is present. In the centre of H -zone, M-line is present, formed by the threats that connect the myofilaments.