Iron Metabolism & Heme Synthesis MCQ Quiz | Nutrition

1. Where is dietary non-heme iron (Fe3+) primarily reduced to its ferrous form (Fe2+) for absorption?

2. Which protein is the primary transporter of iron in the plasma?

3. The major intracellular iron storage protein, which is also a useful serum marker for total body iron stores, is:

4. Which hormone, synthesized by the liver, is the master negative regulator of systemic iron homeostasis?

5. The rate-limiting step in heme synthesis is catalyzed by which enzyme?

6. The initial and final steps of heme synthesis occur in which cellular compartment?

7. The final step of heme synthesis, the insertion of Fe2+ into protoporphyrin IX, is catalyzed by:

8. Which of the following laboratory findings is most characteristic of iron deficiency anemia?

9. Hereditary hemochromatosis, a condition of iron overload, is most commonly caused by a mutation in which gene?

10. Acute Intermittent Porphyria (AIP) is caused by a deficiency in which enzyme of the heme synthesis pathway?

11. Lead poisoning inhibits heme synthesis by targeting which two enzymes?

12. The transport of iron out of enterocytes and macrophages into the plasma is mediated by:

13. The “mucosal block” theory of iron absorption primarily involves which mechanism?

14. Which vitamin enhances the absorption of non-heme iron by reducing Fe3+ to Fe2+?

15. The two substrates required for the first step of heme synthesis are:

16. Porphyria Cutanea Tarda (PCT), the most common porphyria, is caused by a deficiency in:

17. In the “Iron-Responsive Element / Iron Regulatory Protein” (IRE/IRP) system, what happens when intracellular iron levels are low?

18. The copper-containing enzyme required for oxidizing Fe2+ to Fe3+ before it binds to transferrin in the plasma is:

19. Which of these conditions would lead to decreased hepcidin production?

20. What is the mechanism of action of hepcidin?

21. Anemia of chronic disease is often characterized by:

22. Heme is degraded by heme oxygenase into biliverdin, iron, and which other molecule?

23. In sideroblastic anemia, iron accumulates in which part of the erythroblast?

24. What is the primary role of Divalent Metal Transporter 1 (DMT1) in iron metabolism?

25. The enzyme ALA synthase requires which vitamin as a cofactor?