Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025
Definition
In the context of Anatomy and Physiology, a reactant is a substance that takes part in and undergoes change during a chemical reaction within the body. These changes are fundamental for processes such as metabolism, respiration, and cellular repair.
Related terms
Product: A product is the substance(s) formed as a result of a chemical reaction involving reactants.
Metabolism refers to the set of life-sustaining chemical transformations within the cells of living organisms that allows them to grow, reproduce, maintain their structures, and respond to their environments.
Enzyme: An enzyme is a protein that acts as a catalyst in living organisms, regulating the rate at which chemical reactions proceed without itself being altered or consumed