so does this mean the substrate molcules can take part in reactions more easily??because aren't they broken up already
Take digestion, for example, the enzymes break down the large molecules (eg proteins) into smaller more digestible molecules (eg amino acids).
Without the enzyme, the reactions to break down these molecules would be too slow to maintain life.
The substrate which are being broken down are larger so will be broken down into much smaller components.
The main aim of an enzyme is to break any bonds between the building blocks of a substrate into the smallest component it could be.
The smaller substrate can be absorbed by the body and then used in other reactions (break down of starch/glycogen produces glucose which is used in respiration.)
The breaking down of the substrate is the reaction (breaking down is hydrolysis) (eg ATP hydrase breaking a bond to release energy)
Enzymes are biological catalyst- they increase the rate of reaction without being used up.