Iron Flashcards
How is iron transported in the body?
Transferrin
Where does transferrin synthesis take place?
Liver
Where are transferrin receptors?
In most tissues
Where is ferritin stored?
Liver, spleen, bone marrow and muscle
What is transferrin?
transport protein
Describe 3 functions of transferrin?
Renders Iron soluble,
prevent Iron-mediated free radical toxicity and
facilitates transport into cells.
Name 3 iron balance mechanisms
Continuously reutilisation of Fe from RBC.
Regulation of absorption in intestine hepcidin.
Ferretin iron piggybank (store and release).
How much iron does the body contain
2 to 4 g
Where is the site of haemoglobin syntheses?
Bone marrow
How much Iron does the body absorb daily?
About 10% of dietary intake 1 mg
What form does Iron take in aqueous solution?
Fe2+ is ferrous form and Fe3+ is ferric form. These are oxidation states.
What is haemoglobin and it’s function
A molecule comprising of a protein and heam group its function to carry oxygen from lungs to tissue.
What is Erythrocytes
Red blood cells
What is myoglobin?
Iron containing oxygen storage protein in the muscles
How is iron stored in the body?
Ferritin and haemosiderin
Which form of iron is present in non harm foods?
Fe3+ (ferric form)
How much iron is mandatory fortification of white and brown flour in UK?
> 16.5 mg iron/kg
Which enzyme in the stomach and small intestine release haem from the globin?
Proteases
Why is haemoglobin and myoglobin hydrolysed in stomach and small intestine ?
To allow absorption across the brush border.
Which form of iron is absorbed?
Fe2+ (ferrous).
What inhibits nonheme iron from absorption?
Certain fibres polyphenols and Phytic acid which irreversibly bind Iron in the gastric intestine lumen making it unavailable for absorption.
How does vitamin C help the absorption of iron?
Prevents formation of insoluble and unabsorbable in compounds. Also, reduces ferric to ferrous iron.
name 9 functions of iron
Haemoglobin and myoglobin Electron transport ATP production Amino acid metabolism Niacin synthesis Nitric oxide synthesis Destruction of invading pathogens Carbohydrate metabolism Do you nice synthesis
Name inadequate absorption iron deficiency
Poor bioavailability Antacid therapy or high gastric pH Excess dietary Bran, tannin, phytates or starch. competition from other metals. Bowel resection. Coeliac disease. Inflammatory bowel disease
