role of iron Flashcards
the body contains — grams of iron and our average daily intake is —-
- 2 to 4 grams
- 20mg
ferrous reduced is —-
ferric oxidised form —-
fe+2
fe 3+
the 2 forms of iron gained from our diet is :
the males have – grams of irons
females have —-
while children have —
- haem form foud in hb from animal source and non haem source form from veggies and pulses
- 4 grams
- 3.5
- 3 or less
both haem iron and non haem iron hydrolysed by the enzyme —-
protease
—- in the stomach also aids to release iron from food
HCl
in the stomach most iron is —- which is favoured by —- of the stomach and —– such as vitamin c
- non-heam aka f+3
- low ph
- reducing agent
absorption of the iron in small intestine:
1- iron must be — to enter the body
2- iron enters the body through a cell called —-
- fe+2
- enterocyte
haem iron is entirely absorbed by — via —- this transporter is called —–. Fe+2 ia released from haem by —– in the entrocyte
- enterocyte via transport protein
- haem carrier protein 1
- haem oxidase
non- haem iron at the — of the enterocyte , the fe+3 is reduced by —– to fe+2 , the transport of fe+2 into the enterocyte is via ——
- surface
- reductase caked DcytB aka duodenal cytochrome
- DMT1 aka divalent metal transporter 1 only
iron inside the enterocyte is stored as cystolic iron called —– or transported across the basolateral bottom membrane via —- , the fe+2 is converted back to fe+3 by —- , fe+3 binds to — for transport around the body
-ferritin
-ferroportin FPN
- hephastin
- transferrin
iron absorption is reduced by the presence of :
- tannins
- oxalate
- phylate
- inorganic phosphates
- phosphate containing antacids
iron deficiency anaemia is reduced from —-
poor absorption
iron is transported around the body in the — form as it attaches to —- and it has — affinity for it
fe+3
transferrin
- high
—- refers to the fe+3 absence
apotransferrin
transferrin-bound iron is carried to —-
stores and bone marrow
iron enters the cell by —- via —– and a —- is formed and fe+3 is — and stored as — in the cytoplasm , the aptotransferrin is — to the surface of the cell
- endocytosis
- transferrin receptor
- CURL , compartment uncoupling of receptor
- released
-ferritin - recycled
true or false:
most iron is stored in the ferrous state and it stored as part of the protein complex ferritin
false, ferric state fe+3
protein forms a shll contains — fe+3 in the form of ——- crystals
- 3,000
- Ferric oxide hydroxide crystals FeOOH
summary :
1- iron is transported around the body in the —- form attached to —-
2- iron is stored as part of the protein complex —
3- iron is moved into the cells by —-
4- iron is absorbed at the brush border via —- or haem as —-
5- fe+2 leaves the enterocyte via —
6- fe+2 is oxidised to fe+3 by —-
7- fe+3 binds to —- for transport
- fe+3
- transferrin
- ferritin
- endocytosis
-DMT1 - fe+2
- FPN
- hephaestin
- transferin
the fucntions of iron include :
it serves as a carrier of — to the tissue from the lungs by —–
it acts a transport medium for — within cells
it is an integrated part of —- systems in tissues as cytochrome
- oxygen
- rbc hb
- electrons
- enzymes
read: ( iron diffency )
- Most common micronutrient deficiency
- When iron levels drop:
– Storage iron is mobilised first
– Haemoglobin synthesis is impaired - Results in microcytic hypochromic anaemia
- Treat with
– Iron supplements
read: ( iron overload )
Haemosiderosis:
– Accumulation of ferritin and hemosiderin
– Haemosiderin: iron-storage complex that is composed of partially
digested ferritin and lysosomes
– Leads to free radical generation
* Haemochromatosis:
– Progessive hemosiderosis
– Results in organ damage
– Associated with a mutation in the HFE gene
* Treat with:
– Repeated phlebotomy
– Iron chelator: desferrioxamine
