Hemoglobin, Iron and bilirubin

Question 1

1. Heme is a:
   a. Chelate of iron with the four pyrrole groups of a porphyrin.
   b. Conjugated protein and an oxygen-carrying pigment
   of the erythrocytes.
   c. Protein found in red skeletal muscle that releases
   oxygen.
   d. Colorless compound formed in the intestines by the
   reduction of bilirubin.

Answer 1

a. Chelate of iron with the four pyrrole groups of a porphyrin.

Question 2

2. The role of hemoglobin is to:

a. Transport iron between organs.
b. Store iron and readily release it when body iron
stores are low.
c. Reversibly bind oxygen.
d. Conjugate bilirubin in the liver.

Answer 2

c. Reversibly bind oxygen.

Question 3

3. What is bilirubin conjugated to in a hepatocyte to form
   conjugated bilirubin?

a. Cholic acid
b. Glycogen
c. Bile acid
d. Glucuronic acid

Answer 3

d. Glucuronic acid

Question 4

4. In an individual with suspected β-thalassemia, which of
   the following laboratory results would correctly indicate
   the presence of this disease?

a. Increased hemoglobin concentration, mean corpuscular
volume (MCV) and mean corpuscular hemoglobin
concentration (MCHC) with the peripheral blood
smear showing increased macrocytes and Howell–Jolly
bodies
b. Decreased hemoglobin concentration, MCV and
MCHC with the peripheral blood smear indicating
microcytosis, target cells, and polychromasia
c. Decreased hemoglobin concentration, increased
MCV and MCHC and persistence of hemoglobin F
with the peripheral blood smear indicating spherocytosis and nucleated red blood cells
d. Increased hemoglobin concentration and normal MCV
and MCHC with a normal peripheral blood smear

Answer 4

b. Decreased hemoglobin concentration, MCV and
MCHC with the peripheral blood smear indicating
microcytosis, target cells, and polychromasia

Question 5

5. Which of the following is associated with low serum iron
   and high total iron binding capacity (TIBC) or transferrin?

a. Hemochromatosis
b. Iron-deficiency anemia
c. Iron intoxication
d. Anemia of chronic disease

Answer 5

b. Iron-deficiency anemia

Question 6

6. This readily soluble iron/protein complex is the form in
   which iron is stored in tissues:

a. Ferritin
b. Transferrin
c. Hemosiderin
d. Hemoglobin

Answer 6

a. Ferritin

Question 7

7. The correct formula for determining the percent of transferrin saturation % is:

a. MCV <70 mL = increased transferrin
b. Total iron binding capacity ÷ serum iron
c. Total iron binding capacity × 100
d. [Serum iron: TIBC] × 100

Answer 7

d. [Serum iron: TIBC] × 100

Question 8

8. The major difference between thalassemia and hemoglobinopathy is that:

a. In thalassemia the globin chains of hemoglobin are
structurally altered.
b. In thalassemia the serum level of conjugated bilirubin is dramatically increased.
c. In a hemoglobinopathy the globin chains of hemoglobin are structurally altered.
d. In a hemoglobinopathy the globin chains of hemoglobin are insufficiently produced

Answer 8

c. In a hemoglobinopathy the globin chains of hemoglobin are structurally altered.

Question 9

9. Anemia of chronic disease is characterized by:

a. Elevated transferrin saturation (TSAT) and elevated
or normal ferritin
b. Elevated TSAT and low or normal ferritin
c. Low TSAT and low or normal ferritin
d. Low TSAT and elevated or normal ferritin

Answer 9

d. Low TSAT and elevated or normal ferritin

Question 10

10. Symptomatic hereditary hemochromatosis is best characterized by:

a. Elevated TSAT and elevated ferritin
b. Normal TSAT and elevated ferritin
c. Elevated TSAT and normal ferritin
d. Normal TSAT and normal ferritin

Answer 10

a. Elevated TSAT and elevated ferritin

Question 11

11. Hemolytic disease in a newborn results from maternal-fetal Rh incompatibility. This produces physiological
    jaundice that is characterized by:

a. Unconjugated hyperbilirubinemia.
b. Conjugated bilirubinemia.
c. Hemosiderosis.
d. Hemoglobinopathy

Answer 11

a. Unconjugated hyperbilirubinemia.

Question 12

12. Extrahepatic biliary atresia:

a. Is characterized by the lack of bile ducts within the liver.
b. Is less common than intrahepatic biliary atresia.
c. Is characterized by a mixed hyperbilirubinemia.
d. Produces jaundice that can be observed within the
first few days of life.

Answer 12

c. Is characterized by a mixed hyperbilirubinemia.

Question 13

13. Bilirubin:
    a. In the conjugated form is highly toxic to the nervous
    system when elevated.
    b. In the plasma is bound to albumin before conjugation in hepatocytes.
    c. Becomes conjugated to cholic acid in the hepatocyte.
    d. All of the above

Answer 13

b. In the plasma is bound to albumin before conjugation in hepatocytes.