What term refers to the substance acted upon by an enzyme or ferment?

The term that refers to the substance acted upon by an enzyme is "substrate." In enzymatic reactions, enzymes bind to specific molecules, known as substrates, in order to facilitate a chemical reaction. The unique structure of enzymes allows them to recognize and bind to their corresponding substrates, and this interaction is crucial for the enzyme's function.

Once the substrate binds to the enzyme, it undergoes a transformation, resulting in the formation of products. Understanding the role of the substrate is essential in biochemistry, as it allows for insight into metabolic pathways and the specific actions of enzymes in biological processes. The other terms such as "catalyst," "inhibitor," and "product" each relate to various aspects of enzyme activity but do not define the substance that the enzyme acts upon directly. A catalyst, for instance, refers to a substance that increases the rate of a reaction but is not consumed in the process, while an inhibitor is a substance that decreases enzyme activity, and a product is what results from the enzymatic reaction after the substrate has been processed.