Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

ASC378 > B-Complex Vitamins > Flashcards

B-Complex Vitamins Flashcards

1
Q

Vitamin C types

A

-pantothenic acid
-niacin
-choline
-biotin
-folic acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Nicotinamide

A

niacin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Nicotinic acid is a component of what two coenzymes?

A

-NAD
-NADP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the substance of acid and amide?

A

colorless crystalline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the niacin acid and amide soluble in?

A

water and alcohol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is niacin resistant to?

A

heat, air, light, and alkali
(stable in foods)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Man, dog, rat, and pig metabolism leads to the excretion of _______ __________

A

methylated compounds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the nicotinic acid and nicotinamide excreted in ruminants?

A

unchanged

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What does poultry conjugate 2 molecules of nicotinamide with?

A

ornithine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is niacin present as in animal tissues?

A

pyridine nucleotides (free niacin is not present in the tissues)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What does NAD serve as in the TCA cycle?

A

the electron acceptor in 3 of the 4 dehydrogenation steps

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

NAD and NADP function in biological oxidation-reduction systems via their ability to serve as _______ _______ _______

A

hydrogen transfer agents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Niacin deficiency symptoms

A

-black tongue in dogs
-pellegra in humans
-casal’s necklace

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Black tongue

A

-deficiency symptom of niacin in dogs
-black colorization of tongue
-loss of appetite
-diffuse inflammation of gums
-tissues become neurotic and eroded
-bloody diarrhea caused by GI mucosa infammation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Pellegra

A

-deficiency symptom of niacin in humans
-dermatitis of skin exposed to light
-loss of appetite
-nausea
-fiery red tongue caused by inflammation of mucous membranes
-delirium and hallucinations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Casal’s necklace

A

-deficiency symptom of niacin
-reddened area around the neck when sunlight hits it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Where does adequate synthesis of niacin occur?

A

in ruminants in the rumen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Niacin relationship with corn

A

-corn is low in the amino acid tryptophan
-niacin in corn is in a bound form that is unavailable to the rat, pig, or poultry without alkali treatment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is needed for niacin synthesis?

A

tryptophan
-60 mg TRP required for synthesis of 1 mg of niacin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Niacin assay

A

microbiological because tryptophan does not interfere with it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Sources of niacin

A

-animal and fish by-products
-distiller’s grains
-yeast
-alfalfa
-present in cereals but low availability
-widespread in feeds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Pantothenic acid is a constituent of _______

A

coenzyme A (coenzyme for acetylation)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Coenzyme A contains

A

-pantothenic acid
-adenosine-3 phosphate
-pyrophosphate
-B-mercaptoethylamine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Pantothenic acid exists in the tissues as:

A

-free pantothenic acid
-coenzyme A (bound form)
-pantothenyl phosphate
-pantotheine phosphate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is pantothenic acid normally sold as?

A

Ca pantothenate salt

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Pantothenic acid is sensitive to _____, ______, and _______

A

acid, base, and heat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

As a constituent of coenzyme A what is pantothenic acids function?

A

necessary in various acetylations of the 2 carbon fragments that arise from metabolism of fats, CHO, and amino acids to form acetyl CoA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Functions of pantothenic acid

A

-serves in fatty acid synthesis
-functions in steroid synthesis
-acetylation of choline
(choline + Acetyl CoA —> acetylcholine)
-1st step in heme porphyrin synthesis is the condensation of glycine and succinyl CoA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

General deficiency symptoms of pantothenic acid

A

-nervous disorders
-dermatitis (especially in poultry around eyes and mouth)
-graying of black hair in rats, dogs, and foxes (achromotrichia)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Metabolic deficiency symptoms of pantothenic acid?

A

-reduced pyruvate utilization
-decreased cholesterol synthesis
-altered energy conversion and CHO utilization
-reduced antibody production
-nerve involvement (due to acetylcholine)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Two antimetabolites of pantothenic acid

A

-pantoyltaurine
-methylpantothenic acid
(normally only have a deficiency if antimetabolites are present)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Pantothenic acid assay’s

A

no suitable chemical methods
-general bioassays carried out on depleted rats and chicks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Sources of pantothenic acid

A

-yeast
-liver
-eggs
-alfalfa hay
-molasses
-wheat bran

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What/who synthesizes pantothenic acid?

A

-green plants
-some microbes
-practical diet deficiency is rare

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What can be substituted as biotin in nutrition?

A

oxybiotin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What form in nature and natural products does biotin usually occur in?

A

bound form (biocytin)

37
Q

What does a mammalian enzyme do to the bound form of biotin?

A

cleaves it into equimolar amounts of biotin and lysine
-most biotin is bound to protein or high molecular weight peptides

38
Q

Primary function of biotin

A

it serves as the prosthetic group for a series of enzymes that incorporate CO2 into organic linkage

39
Q

Biotin is very important in _________ ________

A

propionate metabolism (especially in ruminants)

40
Q

What synthesis does biotin play a role in?

A

fatty acid synthesis

41
Q

What causes deficiency symptoms of biotin?

A

-feeding raw egg white
-use of biotin-free diets plus a sulfa drug (prevents intestinal synthesis)

42
Q

Deficiency symptoms of biotin

A

-dermatitis (due to overactivity of sebaceous glands)
-loss of hair
-poor growth
-spectacled eye factor (loss of hair around eyes specifically)
-problems in normal hoof growth

43
Q

Antagonist of biotin

A

Avidin

44
Q

Avidin

A

a protein in egg white, combines with biotin to prevent its absorption
-biotin is released by denaturation of the protein with steam, heat (frying eggs), or UV irridation

45
Q

Which assay is best for biotin?

A

rat bioassay
-can use chicks but they have a higher biotin requirement

46
Q

What synthesizes biotin?

A

intestinal microflora in substantial qualities
-rumen synthesis supplies needs of cattle and sheep

47
Q

What diet usually causes a biotin deficiency?

A

synthetic diet

48
Q

Sources of biotin

A

-yeast
-organ meats
-seeds of plants
-molasses
-milk

49
Q

Does choline qualify as a vitamin?

A

No, because it is a structural component of fat and nerve tissue and is not known to participate in any enzyme system

50
Q

Function of choline

A

functions as a part of acetylcholine - it is involved in nerve transmission

51
Q

What is choline a donor of?

A

methyl groups-mediated through its role in forming S-adenosylmethionine (methyl donor for various reactions)

52
Q

What is choline a constituent of?

A

-lecithin - promotes mobilization of fat from the liver
-sphingomyelin
-found in abundance in the myelin sheaths of nerves
-examples of phospholipids

53
Q

How does the function of choline differ from that of the other B vitamins?

A

it is essential as a structural component of tissues rather than as a metabolic catalyst

54
Q

Deficiency symptoms of choline

A

-perosis
-fatty livers
-hemorrhagic kidney
-

55
Q

Perosis

A

slipped tendons in chicks

56
Q

Fatty livers

A

-mobilization of fat from the liver is somehow impaired and abnormal accumulations of fat occurs
-fats are routinely mobilized from the liver as lipoproteins containing: free fatty acids, fatty acids esterified to glycerol, fatty acids esterified to cholesterol, choline-containing phospholipids

57
Q

What material is capable of contributing methyl groups for choline synthesis?

A

-lipotropic materials = capable of preventing or correcting fatty livers or a choline deficiency

58
Q

Hemorrhagic kidney

A

-blood fails to leave the kidney at a normal rate
-hypertension may happen due to constriction in kidney blood vessels
-deficiency in choline in early life may result in inadequate phospholipids necessary to build the structure of the kidneys and/or their blood vessels

59
Q

What can synthesize choline?

A

the body can synthesize some choline endogenously from phosphatidyl serine + S-adenosylmethionine —> lecithin

60
Q

Sources of choline

A

-all naturally occurring fats
-all feeds that have a source of fat supply

61
Q

What greatly influences the choline needed?

A

dietary level of methionine

62
Q

Folic acid

A

folacin

63
Q

Folic acid structure

A

tetrahydrofolic acid which serves as the biological carrier for C1

64
Q

What is the biochemical role that folic acid plays?

A

a role in the transfer of one carbon units similar to the role of pantothenic acid plays in 2 carbon unit transfer
-THFA interconversion of glycine to serine
-THFA interconversion of homocysteine and methionine

65
Q

What is folic acid necessary for the formations of?

A

it furnishes methyl groups necessary for the formation of purines (DNA synthesis)

66
Q

Folic acid functions in ________ degeneration

A

histidine

67
Q

What is found in large amounts in the urine of folic acid deficient animals?

A

formiminoglutamic acid

68
Q

What is folic acid deficiency due to?

A

intestinal synthesis

69
Q

To be deficient in folic acid usually an _____________ must be added

A

antagonist

70
Q

What drugs will produce a folic acid deficiency because they compete with parminobenzoic acid

A

sulfa drugs (because parminoenzoic acid is necessary for folic acid synthesis)

71
Q

Deficiency symptoms of folic acid

A

-pernicious anemia (Addison’s anemia)
-sprue - sore mouth, raw tongue, diarrhea, frothy fatty feces
-chicks have retarted growth, poor feathering, depigmentation of colored feathers

72
Q

What is folic acid effective in treating?

A

-anemia of pernicious anemia (but not nervous symptoms only B12 can fix this)
-preventing megaloblastic anemias of pregnancy, infancy, and sprue

73
Q

Sources of folic acid

A

-green, leafy material
-organ meats
-cereals
-animal by-products

74
Q

What synthesizes folic acid?

A

intestines
-usually adequate for most farm animals
-poultry requires dietary source

75
Q

What form and pH is folic acid stable at?

A

-dry form
-at a pH of 6 and above
-pH of 6 and below results in complete destruction

76
Q

What is the preferred assay?

A

-bioassay (chicks)
-microbiology methods can be used

77
Q

Primary source of B12 in nature

A

from microbes

78
Q

Who synthesizes B12

A

neither animals or plants

79
Q

Sources of B12

A

-microbes
-meats
-eggs
-cheese
-milk

80
Q

Where is B12 produced?

A

microbial synthesis in the GI tract

81
Q

Is B12 absorbed in nonruminants?

A

No it is available only as coprophagy

82
Q

Plant products are devoid of B12 unless subject to a __________ _________

A

microbial fermentation

83
Q

Functions of B12

A

-coenzyme in several metabolic reactions
-participates in propionic metabolism in the rearrangement step from methylmalonyl CoA to succinyl CoA
-conversion of homocysteine to methionine
-role in protein synthesis and purine metabolism
-role in the impaired rate of RNA and DNA synthesis in deficiency situations

84
Q

Deficiency symptoms of B12

A

-pernicious anemia in humans
-due to the failure of absoprtion of the vitamin at the gut tissue level
-usually due to insufficient secretion of the intrinsic factor by the gastric mucosal cells
-slow growth
-nervousness
-irritability

85
Q

What is the intrinsic factor necessary for?

A

B12 absorption

86
Q

What can deficiency of B12 in sheep be solved with?

A

injection of Co

87
Q

Vitamin B12 works _________ or ________

A

injected or fed

88
Q

Assay for B12

A

biological or microbiological

ASC378 (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions