Hematology 1: Iron Kinetics

Iron is transported in plasma via:

• Transferrin

• Divalent Metal Transporter 1

• Heme Transporter

• Duodenal Cytochrome B

• None

The total iron-binding capacity (TIBC) of the serum is an indirect measure of which iron-related protein?

• Ferric Ions

• Ferritin

• Transferrin

• None

What is the major metabolically available storage form of iron in the body?

• Hemosiderin

• Heme Iron

• Non-Heme Iron

• Ferritin

• None

What membrane-associated protein in enterocytes transports non-heme

ferrous ions from the intestinal lumen into the enterocytes?

• Heme Transporter

• Divalent Metal Transporter 1

• Ferroportin

• None

Iron is transported out of macrophages, hepatocytes, and enterocytes by what membrane protein?

• Ferroprotein

• Transferrin

• Transferrin Receptor

• Ferroportin

• None

Below are several of the many steps in the process from absorption and transport of iron to incorporation into heme.

Place them in proper order.

i. Transferrin picks up ferric iron.

ii. Iron is transferred to the mitochondria.

iii. DMT1 transports ferrous iron into the enterocyte.

iv. Ferroportin transports iron from enterocyte to plasma.

v. The transferrin receptor transports iron into the cell.

• iii, ii, iv, i, v

• v, iv, i, ii, iii

• ii, i, v, iii, iv

• iii, iv, i, v, ii

The transfer of iron from the enterocyte into the plasma is REGULATED by:

• Transferrin

• Ferroportin

• Hepcidin

• Hephaestin

• None

What is the percent transferrin saturation for a male patient with total serum iron of 63 mg/dL and TIBC of 420 mg/dL?

Is the answer within the reference value?

• 15%, outside RV

• 0.15%, inside RV

• 0.15% outside RV

• 15%, inside RV

Ferroportin is a basolateral protein of:

• Hepatocyte

• Erythrocyte

• Macrophage

• Enterocyte

When the body has adequate stores of iron, the hepatocytes sense that and will increase the production of hepcidin.

Iron exported from the enterocyte into the blood is ferrous and must be converted to the ferric form for transport in the blood.

• First Statement is True, Second Statement is False

• Second Statement is True, First Statement is False

• Both Statements are Correct

• Both Statements are Incorrect