AP BIOLOGY

Detailed explanation-1: -The answer is enzymes. 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 generally lower activation energy by reducing the energy needed for reactants to come together and react. For example: Enzymes bring reactants together so they don’t have to expend energy moving about until they collide at random.

Detailed explanation-4: -Enzymes (and other catalysts) act by reducing the activation energy, thereby increasing the rate of reaction.

Detailed explanation-5: -If the activation energy is lowered, more molecules will have enough energy to be able to collide effectively to make products, so the reaction will go faster. At the end of the reaction, the catalyst will return to its original form.