Question

Immediate source of energy for muscle contraction is

• A. Glucose
• B. GTP
• C. ATP
• D. Creatine phosphate

Answer 1

Answer: (C)

ATP

Muscles have two major proteins actin and myosin. These are mostly contractile proteins. The energy from the hydrolysis of ATP by myosin head is directly used in the power stroke i.e., flexing of myosin head during muscular contraction. ATP is also used during muscle relaxation. In the absence of ATP the myosin head will continue to bind with actin head and the muscle fibre shall remain contracted. So, the correct answer is option C.