Which is true about enzymes? Question 20 options: They act on nonspecific, randomly chosen substrates. After a reaction, they cannot be reused. They can speed up metabolic processes in the body. They cannot change shape.

They can speed up metabolic rate in the body.

Explanation:

Enzyme generaly lower activation energy of the substrate so that the rate of chemical reaction cam be increased.

This characteristics of enzymes makes them to be called organic catalysts.They are responsible for aiding fast completion of most biochemical activities in living organisms.

They usually react with specific substrates with their specific Active sites.

i have no idea what the answer is im sorry.

answer: substrate concentration. enzymes work best when there is a high enough substrate concentration for the reaction they catalyse.