Assertion : Enzymes lower down the activation energy of the reactant molecule to make its transition into product easier. Reason : Enzymes are highly substrate specific catalysts.

Step-by-step solution

Enzymes are highly substrate specific i.e. they catalyze the reaction of a particular substrate only. They facilitate occurrence of a reaction and transition of reactant into product. A chemical reaction S P (where S is the substrate and P the product or products) will take place when a certain number of S molecules at any given instant possess enough energy to attain an activated condition called the 'transition state'. The enzyme combines transiently with the substrate to produce a transient state having a lower