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Nutrition 1 Part 2 > Iron > Flashcards

Flashcards in Iron Deck (66):
1

65% fo the iron in the body is found as a part of ___

hemoglobin

2

Sources of Iron

heme iron
non heme iron

3

Heme iron is derived from

hymoglobin and myoglobin

4

non heme iron is found in

meat
beans, dark green veg, dried fruit
blackstrap molasses
enriched foods

5

heme or non heme iron is only found in animal products

heme iron

6

iron exists in several oxidation states by only two are stable in the body which are;

Fe3+
Fe2+

7

heme iron is hydrolyzed from hemoglobin and myoglobin in the _____

small intestine

8

non hem iron is hydrolyzed from food components by HCL and proteases in the

stomach

9

when heme iron is hydrolyzed in the stomach it releases

Fe3+

10

FeOH3 which may be complexed from Fe3+ in the SI is relatively (Soluble/insoluble)

insoluble

11

______ reduces Fe3+ to Fe2+ in the duodenum

ferric reductase

12

______ is needed as a cofactor for ferric reductase activity

vitamin c

13

heme iron is absorbed throughout the

small intestine

14

non heme iron is absorbed via____

DMT1 (divalent mineral transporter 1)

15

factors that enhance non heme iron absorption

vitamin c
other organic acids (lactic, citric)
meat, fish, poultry
low iron status

16

_____ strongly enhances the absorption of non heme iron by reducing dietary Fe3+ to Fe2+

vitamin c

17

factors that inhibit iron absorption

phytic acids
polyphenols
oxalates
Ca Zn Cu Mn
nuts
soy, wheat, egg, whey
tea- peppermint, vervain, linden cham, GT
rapid transit time
decreased stomach acidity

18

when iron stores are adequate or high the protein ______ is released from the liver

hepcidin

19

hepcidin promotes the degradation of _____ which results in decreased transport of iron across basolateral membrane

ferroportin

20

low levels of hepcidin when iron store are low ______ ferroprotin levels

increase

21

____ transports iron through the enterocytes

mobilferring

22

_____ is require for Fe to cross the basolateral membrane

ferroportin

23

once iron is in the blood it is attached to the protein_____ for transport to other tissues

transferrin

24

Fe__ leaving the enterocyte must be converted to Fe__

2+
3+

25

the conversion of Fe2+ to Fe3+ is catalyzed by

hephaestin
ceruloplasmin

26

the number of transferring receptors expressed by a cell is determined by the amount of:

intracellular ion

27

iron is primarily stored in the:

liver

28

the two storage protein forms of iron are

ferritin
hemosiderin

29

ferritin is the ______ storage protein for iron

primary

30

ferritin is stable/unstable?

unstable

31

hemosiderin is a degradation product of

ferritin

32

hemosiderin levels increase when

iron overload

33

most plasma iron comes from the degradation of :

hemoglobin
ferritin
hemosiderin

34

functions of iron

oxygen transport and storage
electron transport and energy metabolism
enzymes

35

_____ transports oxygen from the lungs to the rest of the body

hemoglobin

36

____ functions in the transport and short term storage of oxygen in mm cells

myglobin

37

______ are heme containing compounds that sever as electron carriers during the synthesis of ATP int he mitochondiral ETC

cytochromes

38

some important iron dependent enzymes

peroxidases
ribonucleotide reductase
tyroside hydroxylase
monooxygenase

39

iron is primarily excreted in the ____. ____. and ____

blood
bile
desquamated mucosal cells (GIT)

40

iron deficiency is divided into what three leves

storage iron depletion
early functional iron deficiency
iron deficiency anemia

41

iron deficiency anemia results when there is inadequate iron to support normal _____ formation

RBC

42

anemia of iron is characterized as ____ and _____

microcytic
hypochromic

43

mycrocytic anemia means

RBCs are smaller than normal

44

hypochromic anemia means

hemoglobin content is decreased = they look pale

45

sx associated with anemia include

fatigue
tachycardia
arrhythmias
dyspnea

46

why do the symptoms of anemia such as fatigue, tachycardia, arrhythmias,dyspnea arise

reduced hemoglobin content of RBCs causes decreased oxygen delivery to tissues

47

other sx of iron deficiency include

cold intolerance
poor concentration, mood disturbances
angular stomatitis, atrophic glossitis
alopecia, brittle- spoon nails

48

increased risk of iron deficiency in

infants/kids
teens
menstruating females
pregnancy
chronic blood loss
parasitic infections
hypochlorhydria
gastric bypass sugery
celiac dz
vegetarians/vegans
regular intense exercise

49

clinical indications for iron supplementation

restless leg syndrom

50

adverse effects from iron supplementation include

constipation diarrhea
dark tarry stools
n/v
abd discomfort

51

iron supplements are better tolerated when taken____

in smaller divided doses with food

52

there is a high risk for chronic iron toxicity in:

hemochromatosis
thalassemia or sideroblastic anemia
alcoholic cirrhosis

53

what is hemochromatosis

increase iron absorption in the intestines that result in tissue iron overload

54

what is hemochromatosis caused by

genetic mutation in the iron absorption proteins

55

where will iron be deposited in hemochromatosis

joints, liver, heart, pancreas = which will damage these organs = organ failure

56

treatment of hemochromatosis

freq phlebotomy

57

_____ enhances absorption of non heme iron

vitamin c

58

both hephaestin ad cerulopphasmin are ____ dependent enzymes

copper

59

non hem iron and other divalent minerals such as_______compete for a common absorptive pathway

Ca
Zn
Cu
Mn

60

iron deficiency increases ____ absorption.

Lead

61

___ inhibits incorporation of iron int o heme

lead

62

____ sclera is often associated with iron deficiency

blue

63

beeturia may also indicate iron____

deficiency

64

serum ferritin level wil be _____ in early stages of iron deficiency

decreased

65

MCV may be _____ in iron def

decreased

66

RDW may be _____ in iron def

increased