Question

5 - Myosin is an enzyme that can convert chemical energy into mechanical energy. In what form is the chemical energy stored? In what form does the mechanical energy get expressed? Illustrate in a four-step drawing how the chemical energy is converted to mechanical energy.

Answer 1

Myosins are motor proteins that have ATPase activity. Myosins help in the movement of actin filament by utilising energy released after ATP hydrolysis. Conversion of chemical energy of the ATP molecules into mechanical energy by the myosins help in muscle contraction during movement.
Myosin molecules are composed of head, neck and tail domains. Myosin head has the ATPase activity and during muscle contraction myosin head binds to the actin filament and ATP. Energy from the ATP hydrolysis helps in the bending of myosin head and provide the force to walk along the actin filament.

Myosin heads split ATP and become reoriented and energized myosin S heads bind to actin torming crossbridges SOATP JOApp APP 4 As myosin neads, bind ATP the cross bridges, detach. from the actin. ATP 08280 & Myosin heads rotate toward center of the sarcomere cpower stroke),