Micronutrients

Question 1

what are vitamins?

Answer 1

group of chemically unrelated organic compounds
‘vital amines’

Question 2

how many essential vitamins is there for regulation of body processes and normal metabolic function?

Answer 2

13

Question 3

what does vitamin deficiencies result in?

Answer 3

multiple systemic complications and are linked to oral conditions

Question 4

why are vitamins essential to humans?

Answer 4

we can’t make them

Question 5

what are the exceptions to the fact we can’t make vitamins?

Answer 5

vitamin D = synthesised in the skin upon exposure to sun
vitamin K, some B vitamin = synthesised by gut flora

Question 6

what vitamins occur in food as precursors?

Answer 6

• beta carotene converted to vitamin A
• tryptophan converted to niacin

Question 7

what vitamins are fat soluble?

Answer 7

A
D
E
K
pantothenic acid B5
folate

Question 8

what vitamins are water soluble?

Answer 8

C
& B vitamins:
thiamin
niacin
vit B6
vit B12
riboflavin
biotin

Question 9

what are the features of fat soluble vitamins?

Answer 9

• found with fat in food
• absorbed in lymph, transported attached to protein, stored in liver or in fatty tissues
• excessive intake

Question 10

what are the features of a water soluble vitamin?

Answer 10

absorbed directly into bloodstream, transported in free form, higher turnover in the body with little storage
- prone to leaching from food, more sensitive to heat
- generally not harmful in high doses can be harmful

Question 11

what factors influence the utilisation of vitamins?

Answer 11

1. availability
2. antivitamins
3. provitamins
4. biosynthesis in gut by bacterial flora
5. intestinal disease

Question 12

how many essential minerals are there?

Answer 12

15 to 16

Question 13

what are the main functions of essential minerals?

Answer 13

1. constituents of bones and teeth
   = calcium, phosphorus and magnesium
2. formation of soluble salts the help to control composition of bodily fluids
   = sodium, potassium and chlorine
3. essential components of many enzymes and other proteins, necessary for release and utilisation
   = iron and zinc

Question 14

some minerals are soluble in water and others are insoluble. name 2 of each?

Answer 14

soluble = Na, K
insoluble = Fe, Zn

Question 15

describe the bioavailability of minerals?

Answer 15

?????

Question 16

what is the most common minerals that have deficiencies in the population?

Answer 16

iron and iodine

Question 17

give examples of preformed vitamin A.

Answer 17

retinol
retinaldehyde
retinoid acid

Question 18

give examples of provitamin A.

Answer 18

carotenoids
= beta-carotine
alpha-carotine
lutein
lycopene
beta-cryptoxanthin

Question 19

what is the ratio of beta carotene to vitamin A?

Answer 19

1:6

Question 20

where is provitamin A found?

Answer 20

pigments in plants (orange and yellow)

Question 21

what is the most potent source of vitamin A?

Answer 21

beta-carotene

Question 22

what are the functions of vitamin A?

Answer 22

growth and normal development
vision
regulation of gene expression
antioxidant
immunity
red blood cell production
cell differentiation
- tooth development, oral epithelial development

Question 23

where is preformed vitamin a absorbed as retinol found in the diet?

Answer 23

liver
fatty fish
eggs
whole milk
cheese
butter

Question 24

where ate carotenes (vitamin A) found?

Answer 24

dark green, leafy vegetables, red and orange fruit and vegetables eg carrots/ apricots

Question 25

how does a deficiency in vitamin A effect the teeth?

Answer 25

decreases oral epithelial tissue development impaired tooth formation enamel hypoplasia presence of periodontitis

Question 26

how does a deficiency in vitamin A lead to increased susceptibility of infection?

Answer 26

- ↓ production of mucopolysaccharides & mucus, & ↑ tissue keratinization (e.g. xerophalmia) - decreased anti-bacterial action of macrophages - decreased production of lysozyme - lymphocyte and antibody action also affected

Question 27

how does a deficiency in vitamin A effect bone growth and development?

Answer 27

- Impaired embryological development (possible malformations) - Impaired gene expression & cell differentiation (possible link with cancer) - Impaired bone growth - infertility in males, low rates of conception in females

Question 28

what happens if over 200mg of vitamin A is ingested?

Answer 28

vomiting, headaches, blurred vision, vertigo, shedding skin, uncoordinated muscle movements

Question 29

what would happen if an adult ingested 10mg of vitamin A per day for one month?

Answer 29

bone and muscle pain, headaches, alopecia, liver toxicity, poor muscle coordination