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Regulation of Iron Uptake
Quiz
 
Regulation of iron uptake occurs at the basal membrane of the intestinal mucosal cells. These cells make an iron-binding protein, apoferritin.

In the iron-depleted state little apoferritin is made; iron passes through the cells freely and enters the plasma.

In the replete state more apoferritin is synthesized.

  • Iron is trapped in the cells as ferritin; ferritin can bind up to 3000 iron atoms per molecule of protein.
  • As the mucosal cells turn over and slough, the iron is lost into the intestinal lumen with no absorption.
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