Certified Dietary Manager (CDM) Practice Exam

What role do enzymes play in the body?

1. Transport nutrients

2. Provide energy

3. Speed up chemical reactions

4. Store fats

The correct answer is: Speed up chemical reactions

Enzymes play a critical role in the body by speeding up chemical reactions. They act as biological catalysts, which means they lower the activation energy required for these reactions to occur, thus increasing the rate at which they happen. This is essential because many biochemical processes, such as digestion and metabolism, would occur too slowly to sustain life without the action of enzymes. For instance, in the digestive system, enzymes break down food into smaller molecules that can be absorbed and utilized by the body. By facilitating these reactions, enzymes enable the efficient use of nutrients, support metabolic processes, and regulate various biological functions. The other roles mentioned do not align with the primary function of enzymes. While certain proteins may transport nutrients or store fats, these functions are not related to the enzymatic activity of speeding up reactions. Providing energy is primarily the role of macronutrients like carbohydrates, fats, and proteins, rather than enzymes themselves. Thus, the role of enzymes is distinctly centered on the acceleration of chemical reactions necessary for life.