When a piece of liver is dropped into hydrogen peroxide, the peroxide bubbles vigorously as the hydrogen peroxide (H2O2) decomposes into water (H2O) and oxygen (O2) This range change in reaction rate suggests that liver is a substrate for hydrogen peroxide

that liver contains lots of germs

the liver contains an enzyme that breaks down hydrogen peroxide

that hydrogen peroxide is a powerful enzyme

Lactase is essential for digesting lactose in milk. this enzyme is specific for this sugar. why? molecules and active sites vary in size; only properly sized molecules can fit.there is a precise compatibility between the active site and the lactose molecule.specificity refers to the action of the enzyme, such as hydrolysis, and relatively few molecules can be hydrolyzed.reaction-specific enzymes assume a fit by folding around the most numerous substrate molecules.