Iron Metabolism

Question 1

How much iron is in the body

Answer 1

4gm

Question 2

How much iron is in haemoglobin, liver and myoglobin

Answer 2

65%, 15-30%, 4%

Question 3

How much iron is lost in females and males respectively

Answer 3

1.3 and 0.6

Question 4

Where is iron metabolized

Answer 4

Duodenum

Question 5

True or False, iron is absorbed in the ferric state than the ferrous state

Answer 5

False, it is the Ferrous state

Question 6

True or False, Rate of absorption varies directly with Erythropoiesis and indirectly with Iron store

Answer 6

True

Question 7

What is Iron Metabolism transported by

Answer 7

Transferrin

Question 8

What factors favour iron absorption

Answer 8

Ferrous form 
Inorganic Iron
Acids- HCl, Vitamin C
Solubilizing agents eg sugars, amino acids 
Iron deficiency 
Increased erythropoiesis 
Pregnancy 
Primary Haemochromatosis

Question 9

Who’s factors reduce absorption

Answer 9

Ferric form
Organic Iron
Alkalis- antacids, pancreatic secretions
Precipitating agents- phyates, phosphates 
Iron excess
Decreased erythropoiesis 
Infection 
Yea
Desferrioxamine

Question 10

What enzyme reduces Ferric to Ferrous state

Answer 10

Ferrireductase enzyme called duodenal cytochrome b (DCYTB)

Question 11

What vitamin facilitates the reduction of ferric to ferrous state

Answer 11

Vitamin C

Question 12

Ferrous Iron is transported into the cell via _______

Answer 12

Divalent metal transporter DMT1

Question 13

Iron is transported into circulation via _______

Answer 13

Ferroportin

Question 14

What substance oxidizes the ferrous ion back to it’s ferric state

Answer 14

Hephaestin

Question 15

What substance is produced when iron is abundant

Answer 15

Hepicidin

Question 16

What glycoprotein produces Hepicidin

Answer 16

Hepatocytes

Question 17

What hormone is produced to inhibit entry into the plasma

Answer 17

Hepcidin

Question 18

What organ produces Hepicidin

Answer 18

Liver

Question 19

What disorder in iron metabolism occurs in excess iron absorption, saturation of iron binding proteins and depositions of hemosiderin in the tissues

Answer 19

Hemochromatosis

Question 20

Explain the development of the Bronze diabetes condition

Answer 20

Iron deposition in liver leads to cirrhosis in the pancreas which causes diabetes. The excess iron deposition leads to a bronze pigmentation of the organs and skin,

Question 21

_____ plasma concentrations restricts (hypoferremia) uptake by ______, limiting _______ causing anaemia

Answer 21

Low, Erythrocytes precursors, haemoglobin synthesis