In a catalytic cycle, which of the following is true about the catalyst?

A cofactor is essential for some enzymes to function properly. One type of cofactor is the organic molecules known as coenzymes. Most coenzymes are derived from vitamins. If coenzymes have an important role in various catalysis, why should overconsumption of vitamins be avoided?

Identify the model for enzyme-substrate interaction that suggests that the enzyme and the substrate have complementary geometric shapes that fit exactly into one another.

Oxygen acts as an allosteric regulator of  _______________.

Select the appropriate labels for A, B, and C in the given figure.