Cross bridge formation

Formation of cross bridge is essential for muscle contraction and it dissociate repeatedly, so as to interdigitate thin filaments with thick filaments and shorten the sarcomeres so that muscle contraction occur. Cross bridge is formed from connections between the F-actin of thin filaments and the myosin heads of thick filaments. The myosin heads bind to the specific actin subunit. When it is in its high energy state, it change in shape that pull the thin filament and break its connection to the thin filament and links with another site farther along the thin filament towards the Z line.