NEET BIOLOGY

Detailed explanation-1: -The ATPase site is about 5 nm from the tip of the myosin head and is about 4 nm away from the actin-binding site of myosin. This is the first report of the three-dimensional location of an enzyme active site by electron microscopy.

Detailed explanation-2: -Final Answer:-ATPase enzyme needed for muscle contraction is located in Myosin.

Detailed explanation-3: -ATP on hydrolysis provides energy for the contraction of actin and myosin protein. Not only myosin but also ATPase enzyme acting as a site for action binding. Therefore by the above evidence, we came to know that myosin has ATPase enzyme. Hence the correct answer is option ‘D’ i.e, myosin.

Detailed explanation-4: -Each meromyosin has two important parts, a globular head with a short arm and a tail, the former being called the heavy meromyosin (HMM), and the light meromyosin (LMM). The globular head is an active ATPase enzyme and has a binding site for ATP and an active site for actin. Thus, option B is the correct answer.

Detailed explanation-5: -Myosin is an ATPase that converts chemical energy into directed movement via its cyclic interactions with actin filaments in all eukaryotic cells and can be viewed as a molecular motor[1].