Deck 11: Iron Kinetics and Laboratory Assessment

Question 1

What is the plasma carrier protein for iron?

A)apoferritin
B)apotransferrin
C)albumin
D)hemosiderin

Answer 1

apotransferrin

Question 2

The serum ferritin is used more often than bone marrow or liver biopsies to assess iron stores because it is

A)a more direct measurement.
B)more accurate.
C)more precise.
D)less invasive.

Answer 2

less invasive.

Question 3

What is the mechanism for iron toxicity if iron is present in excess amounts?

A)acts as a catalyst in forming hydroxyl (free) radicals
B)impedes hematopoiesis
C)reduces hemoglobin to methemoglobin
D)interferes with globin synthesis

Answer 3

acts as a catalyst in forming hydroxyl (free) radicals

Question 4

Which of the following is true for apotransferrin?

A)It can bind two molecules of ferric iron.
B)It binds to a ferritin receptor found on the cell membrane.
C)It is synthesized in the kidney.
D)It is normally about 50% saturated with iron.

Question 5

Which two organs are the major storage sites for iron in a normal individual?

A)lymph nodes and muscle
B)bone marrow and pancreas
C)spleen and heart
D)liver and spleen

Question 6

Soluble transferrin receptor (sTfR)levels increase when intracellular iron levels are

A)decreased.
B)elevated.
C)constant.
D)both a and b.

Question 7

A patient has a serum iron of 10 g/dL and a total iron-binding capacity (TIBC)of 490 g/dL.What is the percent saturation of transferrin?

A)2%
B)25%
C)40%
D)60%

Question 8

Which of the following stains blue with the Prussian blue stain?

A)ferritin
B)hemosiderin
C)transferrin
D)both ferritin and hemosiderin

Question 9

The serum iron and TIBC results given in Question 7 are consistent with:

A)iron overload.
B)iron toxicity.
C)iron deficiency.
D)acute infection.

Question 10

Select the condition where an acute increase in ferritin levels can be detected without a specific increase in the amount of systemic body iron?

A)myocardial infarction
B)bacterial infection
C)malignancy
D)liver disease

Question 11

Where is the largest percentage of iron in the body located?

A)stored in the bone marrow
B)stored in the liver
C)attached to hemoglobin in erythrocytes
D)in the cytoplasm of macrophages

Question 12

Acute (24-hour)assessment of the amount of iron that is available for hemoglobin production is best identified by measuring the

A)sTfR levels on the cell membrane.
B)amount of hemoglobin in reticulocytes.
C)amount of hemosiderin with Prussian blue stain.
D)zinc protoporphyrin levels in red blood cells.

Question 13

Good dietary sources of iron include all except

A)meat.
B)fruit.
C)fortified flour.
D)legumes.

Question 14

Heme is composed of iron and

A)globin chains.
B)oxygen.
C)methemoglobin.
D)protoporphyrin IX.