Multiple choice

In erythroid cells, which of the following enzymes regulates heme synthesis?

  1. ALA synthase

  2. ALA dehydratase

  3. Protoporphyrinogen oxidase

  4. Ferrochelatase

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Ferrochelatase is the final enzyme in the heme biosynthesis pathway, inserting iron into protoporphyrin IX to form heme. ALA synthase, while rate-limiting, is not considered the regulatory enzyme in erythroid cells where feedback inhibition by heme is less prominent.