Sarcomere Structure Notes

Sarcomere Structure

• Sarcomere: The basic contractile unit of muscle fiber, composed of myofilaments.

• A Band:

  • Description: Darker staining band located in the center of each sarcomere.
  • Composition: Contains both actin (thin filaments) and myosin (thick filaments).

• H Zone:

  • Description: Central region of the A band.
  • Composition: Contains only myosin filaments, without any overlapping actin.

• M-Line:

  • Description: The middle of the H zone.
  • Function: Contains protein filaments that serve to hold myosin filaments in place, maintaining the structural integrity of the sarcomere.