The part of the enzyme where the substrate fits is known as the active site isomer position activation site none of these

The sodium channel are unable to open due to dehydration.

Explanation:

Dehydration may be defined as the medical condition in which body water content and fluid loss out from the body. The sodium ions are lost in large amount due to dehydration.

The sodium ions is important for the propagation of action potential. The opening of sodium and potassium channel causes the end plate potential. The lose of sodium ion hinders the opening of sodium channels and causes imbalance in the body. This imbalance and opening of sodium channel at different rate causes muscle cramping in the body.