Multiple choice

What is the direct source of energy for muscle contraction?

  1. ATP

  2. ADP

  3. Glucose

  4. Food

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Adenosine triphosphate (ATP) is the direct chemical energy source used by myosin heads to bind, pull, and release actin filaments during muscle contraction. While glucose and food are ultimate sources of energy, they must first be converted into ATP.