Iron is absorbed from:
Ans. (a) Duodenum with fast clearanceRef: Harrison 18th edition, Chapter 103* Iron absorbed from the diet from the duodenum or released from stores circulates in the plasma bound to transferrin.* The turnover of transferrin-bound iron is very rapid typically 60-90 min.* Because almost all of the iron transported by transferring is delivered to the erythroid marrow, the clearance time of transferrin-bound iron from the circulation is affected most by the plasma iron level and the erythroid marrow activity.* When erythropoiesis is markedly stimulated, the pool of erythroid cells requiring iron increases and the clearance time of iron from the circulation decreases. The half- clearance time of iron in the presence of iron deficiency is as short as 10-15 minutes.
Duodenum with fast clearance
Jejunum with fast clearance
Ileum with low clearance
Bone marrow
Anemia and RBC Disorders