Locomotion and Movement Question 28

28. ATPase enzyme needed for muscle contraction is located in

(a) actinin

(b) troponin

(c) myosin

(d) actin

Show Answer

Answer : c

Hints & Solutions

(c) ATPase enzyme is located in the myosin cross bridge heads. Actin forms the light or I- Band. Actin slides over myosin during contraction. Troponin protein is involved in establishing connection with myosin cross bridges. Actin is not involved in muscle contraction. It is also an ATPase (an enzyme) which is activated by $Ca^{2+}$ and $Mg^{2+}$ ions. Hence, ATPase enzyme is located in myosin.