Question

which of the following statements about enzymes is true: a) they are carbohydrates b) they are not reuseable c) they are required in large amounts d) they are stable at high temperatures e) they are biological catalysts

Answer 1

e)

Answer 2

e

Answer 3

Well... if you care about knowing why...

a) Is not true because enzymes are proteins (or amino acid chains/polypeptides) formed and folded in a way that makes chemical changes occur faster in the cell.
b) Enzymes can be reused as long as they arent destroyed.
c) Since a single enzyme can only catalyze one chemical reaction at the time (a la lock and key model), you need lots of them to change the rate significantly.
d) SOME enzymes are stable at high temperatures. BUT since they are proteins, if the temperature gets too high they change (like how meat changes when it's cooked).

... and enzymes are biological catalysts, so that's the answer!