LIFE SCIENCE

Detailed explanation-1: -Definition. An enzyme is a biological catalyst and is almost always a protein. It speeds up the rate of a specific chemical reaction in the cell.

Detailed explanation-2: -A substance that speeds up a chemical reaction-without being a reactant-is called a catalyst. The catalysts for biochemical reactions that happen in living organisms are called enzymes. Enzymes are usually proteins, though some ribonucleic acid (RNA) molecules act as enzymes too.

Detailed explanation-3: -Enzymes in our bodies are catalysts that speed up reactions by helping to lower the activation energy needed to start a reaction.

Detailed explanation-4: -Enzymes are proteins that speed up reactions by reducing the activation energy. Each enzyme typically binds only one substrate. Enzymes are not consumed during a reaction; instead they are available to bind new substrates and catalyze the same reaction repeatedly.