Answer:
Muscles are able to contract due to myosin's ability to “break down” (hydrolyze) ATP.
Step-by-step explanation:
In muscle contraction, sarcomere shortening occurs: actin filaments “glide” over those of myosin, thanks to certain binding points that form between these two filaments, leading to the formation of actomyosin.
For this slip to happen, a large amount of two important elements participate: Ca ++ and ATP ions. In this case it is up to the myosin molecule to “break down” (hydrolyze) the ATP, releasing the energy needed for contraction to occur.