In iron metabolism:
- Iron stored in liver cells is transported across cell membranes in the ferrous state.
- The major plasma transport protein for iron is hemosiderin.
- In the form of ferritin, iron may accumulate in mucosal cells of the duodenum.
- Nearly all iron in the diet is absorbed and any excess secreted in the feces.
A, B and C
- A and C
B and D
All of the above
- It is stored in the iron (III) state, and must be reduced to the iron (II) state prior to transport.
- Transferrin is the major iron transport protein.
- Ferritin is an intracellular iron binding (storage) protein.
- Excess is certainly excreted, but it is never absorbed by the body.
Uptake by the intestinal mucosal cells occurs, but in the iron-replete state these iron-rich cells slough.
The iron does appear in the feces.
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