American Society for Clinical Pathology (ASCP) Histotechnologist Practice Test

How is water involved in reactions catalyzed by hydrolases?

1. Water is a substrate

2. Water is a byproduct

3. Water is both added and removed

4. Water is not required

The correct answer is: Water is both added and removed

In reactions catalyzed by hydrolases, water plays a crucial and dual role, making it both a reactant and a product in many of these enzymatic processes. The correct answer emphasizes that water is involved in ways that illustrate its versatility as a reactant in hydrolysis reactions, where it is added to break down substrates. During hydrolysis, water molecules facilitate the cleavage of chemical bonds in larger molecules, leading to the formation of smaller, soluble products. For instance, in the digestion of food, hydrolases break down complex carbohydrates, proteins, and fats, with water being necessary to facilitate these reactions. Moreover, when the reaction completes, there are instances where water can be removed as a byproduct or remain involved in the continued reaction cycle. This reflects the dynamic nature of hydrolase-catalyzed reactions, where water can be part of various stages of the process. Thus, recognizing that water is both added and can be removed during these reactions is essential in understanding the function of hydrolases in biological systems.