lecture 7: vitamins Flashcards
1
Q
vitamin volume in animal diet
A
- present in minute quantities
- effective in small amounts
2
Q
absence or inefficiency in vitamins results in
A
specific deficiency disease or syndrome (e.g. lack of Vit D results in rickets/osteomalacia)
3
Q
examples of vit that are not essential for some species
A
- vit D: most animals can make via capturing UV rays in skin & converting in liver but usually not in sufficient quantities so needs supplimentation
- vit C: ruminants, dogs, & cats can make
- vit K & B vitamins: ruminants can make via microbial fermentation
4
Q
classes of vitamins
A
- fat soluble → body structure
- water-soluble → fxn as cofactors for enzymes in biochemical rxns (metabolism)
5
Q
fat-soluble vitamins
A
- A (retinol) → important for bone formation, vision, epithelial tissue maintenance
- D (ergocalciferol [D2] in plants & cholecalciferol [D3] in animal tissues) → Ca & P absorption for bone formation
- E (⍺-tocopherol) → antioxidant & muscle structure
- K → blood clotting & post-synthesis protein modification
6
Q
water-soluble vitamins
A
- fxn as cofactors for enzymes in biochemical rxns (metabolism)
- C
- B complex:
- thiamine (B1)
- riboflavin (B2)
- niacin (B3)
- pantothenic acid (B5)
- biotin (B7)
- cobalamin (B12)
- folic acid (B9)
- choline (not a vitamin but similar properties to B vit)
7
Q
vitamin units of measurement
A
- water-soluble vit & vit K are measured in weight (mcg or mg)
- vit A, D, & E are measured in international units (IU) = standardizes biological effect of a given substance (measures potency not amount)
- 1 IU of vit E = 1 mg of ⍺-tocopherol acetate = 0.9 mg ⍺-tocopherol (alcohol) → acetate = less potent because you need more of it to have same effect
8
Q
B vitamins
A
- water-soluble
- thiamine (B1)
- riboflavin (B2)
- niacin (B3)
- pantothenic acid (B5)
- biotin (B7)
- folic acid (B9)
- cobalamin (B12)
- choline → not a vit but similar properties to B vit
9
Q
vit A
A
aka retinol = fat-soluble vit important for:
- bone formation
- vision
- epithelial tissue maintenance
10
Q
vit D
A
- fat-soluble vit
- ergocalciferol [D2] in plants
- cholecalciferol [D3] in animal tissues
- critical for Ca & P absorption → fxns in bone formation
11
Q
vit E
A
aka ⍺-tocopherol = fat-soluble vit that acts as antioxidant & fxns in muscle structure
12
Q
vit K
A
fat-soluble vit that fxns in blood clotting & post-synthesis protein modification
13
Q
vit B1
A
thiamine
14
Q
vit B2
A
riboflavin
15
Q
vit B3
A
niacin
(water soluble)