Question

a substance that influences the reaction but does not participate in the reaction is a substrate product reactant catalyst

Explanation:

In chemical reactions, a catalyst is a substance that influences the reaction rate (either speeds up or slows down) without being consumed or participating in the chemical - change itself. Substrates are reactants in biochemical reactions (especially enzyme - catalyzed reactions), reactants are substances that participate in a reaction to form products, and products are the substances formed as a result of the reaction.

Answer:

catalyst