Question

Describe the structure of sarcomere.

Answer 1

Hint: Sarcomere is between the repeating two Z lines and is the part of striated muscle tissue. The sarcomere is termed as a basic unit of striated muscle tissue and skeletal muscles are made of tubular muscle cells myocytes and myofibrils of muscle fibers and are developed by the process called myogenesis. Myofibrils appear on alternate light and dark bands and are composed of repeated sections of sarcomeres.

Complete answer: Sarcomere gives the striated appearance to skeletal and cardiac muscles and was firstly explained by Van Leeuwenhoek. A sarcomere is between two Z lines and surrounding the area of Z line the region of the I-band is present. After the region of I-band there is an area of A-band and A-band contains the entire length of the thick filament. Within the A-band there is an area of H-zone which is paler in color and the H-band has no actin in it. Inside H-band there is another thin line called M-line which is formed by cross-connecting components of the cytoskeleton. The sarcomere is fibrous proteins that work as filaments to help in the movement of muscles during contraction and relaxation. When a muscle contracts or relaxes sarcomere slide past each other which help in facilitating these movements.

Note: Sarcomere helps in facilitating both relaxation and contraction movement of muscles with which overall movement of our body occurs and tropomyosin moved to uncover the binding sites of muscle which help in contraction of muscles and during rest, myosin head is bound to an ATP molecule and no access is given on binding sites. With this process movement of muscles occurs in our body.