Vitamin A

Question 1

what are the three active forms (retinoids)? Vitamin A

Answer 1

retinol, retinal, retinoic acid

Question 2

what are the four functions of the retinol form? Vitamin A

Answer 2

vision, sexual reproduction, bone health, immune function

Question 3

what are the four functions of the retinal form? Vitamin A

Answer 3

vision, sexual reproduction, bone health, immune

Question 4

what two forms can be converted back and forth to one another? Vitamin A

Answer 4

retinol and retinal

Question 5

what are the three functions of the retinoic acid form? Vitamin A

Answer 5

cell differentiation, bone health, immune function

Question 6

retinoic acid is formed from what? Vitamin A

Answer 6

retinal and its irreversible

Question 7

which form is in foods? Vitamin A

Answer 7

retinol

Question 8

which form is from plants (carotenoids)? Vitamin A

Answer 8

retinal

Question 9

what are three other properties besides its function of retinoic acid? Vitamin A

Answer 9

 Excretion product
 Toxic
 Helps skin

Question 10

which form is associated with carotenoids? Vitamin A

Answer 10

retinal

Question 11

how many carotenoids are found in nature? Vitamin A

Answer 11

600

Question 12

how many carotenoids have potential vitamin A activity? Vitamin A

Answer 12

50

Question 13

the carotenoids without activity have what health benefits? Vitamin A

Answer 13

 i.e., Lycopene

 Antioxidant that protects against free radicals that initiate cancer

Question 14

whats the efficiency of conversion of carotenoids? Vitamin A

Answer 14

40%

Question 15

30% of carotenoids are what (what happens to them)? Vitamin A

Answer 15

absorbed intact as pigments and deposit in

fats

Question 16

the excess amounts of carotenoids are what four things? Vitamin A

Answer 16

deep yellow color of palms, ear lobes & soles of feet: xanthosis cutis

Question 17

what masks the carotenoids colors? Vitamin A

Answer 17

chlorophyll

Question 18

what happens to green leaves that expose the carotenoids colors? Vitamin A

Answer 18

i.e., green leaves turn red, yellow in fall

Question 19

what is its function in rats? Vitamin A

Answer 19

reproduction

Question 20

vitamin A and vision deal with what? Vitamin A

Answer 20

Ability of eye to adapt to changes in light is dependent on Rhodopsin (visual purple)

Question 21

what are the three details of Rhodopsin (visual purple)? Vitamin A

Answer 21

 Exposure to light bleaches it to form opsin + retinol

 Changes from cis (bent) to trans (linear) form  Stimulates electrical impulses to brain

Question 22

there is constant need for replenishing for what function? Vitamin A

Answer 22

vision

Question 23

what is Nyctalopia? Vitamin A

Answer 23

Night blindness: lack of vitamin A (retinol); Eye cannot readapt easily to darkness

Question 24

how much is in the eye? Vitamin A

Answer 24

1%

Question 25

what two parts of the skin does it deal with in skin integrity via cell differentiation? Vitamin A

Answer 25

 Mucous membranes of epithelial cells |  Epithelial tissues (eye, mouth, skin, GI, respiratory tract, genitourinary tract) have goblet cells that secrete mucus

Question 26

what do the Epithelial tissues that have goblet cells that secrete mucus do during a cold? Vitamin A

Answer 26

flow increases to wash away virus

Question 27

what is the enzyme used in the Epithelial tissues that have goblet cells that secrete mucus during a cold and what does that enzyme do? Vitamin A

Answer 27

lysozymes: degrades foreign | bacteria

Question 28

what happens to the function of skin integrity via cell differentiation in the cells when there is a deficiency? Vitamin A

Answer 28

cells keratinize  Harden, dry, flake off

Question 29

what happens to the function of skin integrity via cell differentiation in the eyes when there is a deficiency? Vitamin A

Answer 29

cornea dries & hardens Xeropthalmia

Question 30

what happens to the function of skin integrity via cell differentiation in the salivary glands when there is a deficiency? Vitamin A

Answer 30

dry, mouth cracks

Question 31

what happens to the function of skin integrity via cell differentiation in the respiratory tract when there is a deficiency? Vitamin A

Answer 31

cilia dries & lost |  Open to invading organisms

Question 32

what happens to the function of skin integrity via cell differentiation in the skin when there is a deficiency? Vitamin A

Answer 32

hardened eruption around hair follicles | toad skin

Question 33

what happens in the functions of growth (& Reproduction in Rats)? Vitamin A

Answer 33

Attaches to binding proteins in cell nucleus to stimulate | differentiation of cells

Question 34

what happens with its function of growth (& Reproduction in Rats) when there is a deficiency in the skeletal bone? Vitamin A

Answer 34

destroys old bone for remodeling |  Bone overgrowth

Question 35

what happens with its function of growth (& Reproduction in Rats) when there is a deficiency in the teeth? Vitamin A

Answer 35

Malformation

Question 36

what happens with its function of growth (& Reproduction in Rats) when there is a deficiency in the reproduction (rats)? Vitamin A

Answer 36

 Male:No spermatogenesis  Female: Fetal resorption

Question 37

what happens with its function in immunity? Vitamin A

Answer 37

Helps fight infection by maintaining healthy epithelial cells & mucous proteins in intestines & lungs

Question 38

what are the three things that happen to the immunity function with a deficiency? Vitamin A

Answer 38

 Decreased activity of white blood cells (T- lymphoctyes)  Increased risk of dying from measles in children  Increased cancers of epithelial cells

Question 39

what does lycopene reduce the risk of? Vitamin A

Answer 39

Reduced risk prostrate cancer

Question 40

who got toxicity by eating what type of liver? Vitamin A

Answer 40

Explorers ate polar bear liver

Question 41

what are the five toxicity symptoms? Vitamin A

Answer 41

```  Drying, desquamation of skin  Bone abnormalities  Hemorrhage  Liver Failure  Death ```

Question 42

what happens with the toxicity symptom of Drying, desquamation of skin? Vitamin A

Answer 42

Hair loss / skin rash

Question 43

what happens with the toxicity symptom of Bone abnormalities? Vitamin A

Answer 43

Headaches, bone & joint pain

Question 44

what are the two things that happen with toxicity in pregnancy? Vitamin A

Answer 44

Accutane --> Dries skin; Birth Defects

Question 45

when are the effects of toxicity in pregnancy seen? Vitamin A

Answer 45

3 X RDA

Question 46

whats the RDA? Vitamin A

Answer 46

 Men: 900 μg RAE  Women: 700 μg RAE

Question 47

whats the Retinol activity equivalents (RAE)? Vitamin A

Answer 47

1 μg of retinol =1 μg RAE

Question 48

1 μg RAE equals how much beta carotene? Vitamin A

Answer 48

12 μg

Question 49

1 μg RAE equals how much alpha carotene and beta cryptoxanthin? Vitamin A

Answer 49

24 μg

Question 50

what are the scientific names of the food sources? Vitamin A

Answer 50

Preformed Retinol; Proform: Carotenoids

Question 51

what are the four main foods sources? Vitamin A

Answer 51

beef liver, sweet potatoes, carrots, fortified cornflakes