An enzyme is a proteinous substance that acts as biological catalysts and increases the rate of biochemical reactions in the body. Enzymes are specific in nature which is as a result of the structure/shape of its building block (amino acid).
Enzymes speedens the rate of a chemical reaction in living systems, which would normally not occur or occur at a much slower rate, without the presence of an enzyme. Enzymes acts on the reactants called Substrates by binding to them to form products but they are not used up in the reaction. Hence, enzymes are not reactants.
