LIFE SCIENCE

Detailed explanation-1: -Enzymes are proteins They act as catalysts, which means that they make biochemical reactions happen faster than they would otherwise. Without enzymes, those reactions simply would not occur or would run too slowly to sustain life. For example, without enzymes, digestion would be impossible.

Detailed explanation-2: -So, the correct answer is ‘Enzymes are used up in reactions’.

Detailed explanation-3: -The answer is A. Enzymes increase the rate of chemical reaction by lowering activation energy barriers. Enzymes are biological catalysts. Like all catalysts, they function by lowering the activation energy of a chemical reaction, which speeds the rate of the reaction.

Detailed explanation-4: -As well as being highly potent catalysts, enzymes also possess remarkable specificity in that they generally catalyse the conversion of only one type (or at most a range of similar types) of substrate molecule into product molecules.