On page 190 in the EK bio 30 minute exam for Lecture one, question number 22 asks what Cofactors are best described as: The answer is C, metal ions or coenzymes that activate an enzyme by binding tightly to it. My question is, why isn't it also A? Aren't they required for enzyme activity, since on page 12 it says that apoenzymes (enzymes without cofactors) are completely non-functional? That kinda confused me.
Please let me know,
Thanks