Physiology Quiz (Block 1.1)

26 multiple-choice questions with explanations for Physiology, Block 1.1: Biology Block: Cell and Hematology. Free, works offline.

Questions

  1. The α-globin and β-globin gene clusters are located on which chromosomes, respectively?
  2. Adult hemoglobin (Hb A) is a tetramer built from how many α and β chains?
  3. How many amino acids make up a normal α-globin chain?
  4. How many amino acids make up a normal β-globin chain?
  5. A complete, functional hemoglobin molecule contains how many heme groups and globin chains?
  6. Embryonic hemoglobin synthesis begins in yolk-sac erythrocytes at approximately what gestational age?
  7. Which of the following is a normal embryonic hemoglobin?
  8. Fetal hemoglobin (Hb F) synthesis begins in the fetal liver at approximately what gestational age?
  9. By 12 weeks of gestation, which hemoglobin has become the dominant type in the fetus?
  10. Hb Bart's hydrops fetalis results from what α-globin gene deletion pattern?
  11. With no α chains available, which hemoglobin dominates in Hb Bart's hydrops fetalis?
  12. What percentage of Hb A is present in Hb Bart's hydrops fetalis?
  13. Hemoglobin H disease results from deletion of how many α-globin genes, and what abnormal tetramer forms as a result?
  14. A 'silent carrier' of α-thalassemia has which genotype, and what is the clinical picture?
  15. α-thalassemia trait (minor) involves loss of how many α-globin genes, and in what configurations can this occur?
  16. The first step of heme synthesis condenses succinyl-CoA with glycine to form which compound, and which enzyme catalyzes it?
  17. Two molecules of ALA condense in the cytosol to form porphobilinogen. Which enzyme catalyzes this step?
  18. The final step of heme synthesis inserts Fe2+ into protoporphyrin IX. Which enzyme performs this step?
  19. Sickle cell hemoglobin (Hb S) results from what mutation?
  20. Hemoglobin C results from what β-globin mutation?
  21. Hemoglobin E results from what β-globin mutation?
  22. Hb Constant Spring, an α-chain variant of 172 amino acids instead of the normal 141, arises from what kind of mutation?
  23. Hb M variants are characterized by stabilization of methemoglobin (Fe3+) and what functional consequence?
  24. In β-thalassemia, what distinguishes a β+ mutation from a β0 mutation?
  25. δβ-thalassemia (including Hb Lepore) heterozygotes typically show what Hb F level?
  26. During translation of globin mRNA, which codon initiates protein synthesis and which amino acid does it encode?