NEET BIOLOGY

Detailed explanation-1: -Enzymes in our bodies are catalysts that speed up reactions by helping to lower the activation energy needed to start a reaction. Each enzyme molecule has a special place called the active site where another molecule, called the substrate, fits.

Detailed explanation-2: -Enzymes perform the critical task of lowering a reaction’s activation energy-that is, the amount of energy that must be put in for the reaction to begin. Enzymes work by binding to reactant molecules and holding them in such a way that the chemical bond-breaking and bond-forming processes take place more readily.

Detailed explanation-3: -Enzymes (and other catalysts) act by reducing the activation energy, thereby increasing the rate of reaction. The increased rate is the same in both the forward and reverse directions, since both must pass through the same transition state.

Detailed explanation-4: -Enzymes are large proteins that bind small molecules. When bound to an enzyme, the bonds in the reactants can be strained (that is stretched) thereby making it easier for them to achieve the transition state. This is one way for which enzymes lower the activation energy of a reaction.