Quizes

Question 1

during collagen synthesis, vitamin c acts as a reducing agent to keep iron in which state?

Answer 1

ferrous (2+) state (reduced)

Question 2

humans are unable to synthesize vit c because they lack the enzyme l-gulonolactone oxidase

Answer 2

true

Question 3

which essential amino acid is a precursor that the body can use to synthesize niacin (vit b3)?

Answer 3

tryptophan

Question 4

the two main active storage forms of riboflavin in our bodies are FMN and?

Answer 4

FAD

Question 5

most people in the u.s. meet their daily thiamin needs because many grain products are fortified or enriched

Answer 5

true

Question 6

the 4-d’s (dermatitis, diarrhea, dementia, death) what deficiency disease?

Answer 6

pellagra (niacin)

Question 7

which food is rich in thiamin?

Answer 7

pork

Question 8

Deficiency disease for thiamin

Answer 8

beriberi

Question 9

which vitamin is responsible for the yellow-green flow seen in milk?

Answer 9

riboflavin

Question 10

riboflavin is sensitive to uv light and can be destroyed if milk is left in the sun

Answer 10

true

Question 11

vit b5 is primarily known for being a structural component of which essential metabolic molecule?

Answer 11

coenzyme A (CoA)

Question 12

vit b6 (as plp) is essential for reactions which involve transferring an amino group from an amino acid to a keto acid (carbon skeleton)

Answer 12

transamination

Question 13

which neurotransmitter is synthesized from acetyl-coa (vit b5) and choline?

Answer 13

acetylcholine

Question 14

in fatty acid metabolism, what is a primary role of coenzyme a

Answer 14

it activates fatty acids by converting them to fatty acyl-coa

Question 15

pantothenic acid (vit 5) is highly toxic, and consuming slightly more than the RDA causes severe liver damage.

Answer 15

false

Question 16

which specific transporter is used for the absorption fo pantothenic acid (b5) in the intestine, a system shared with biotin and lipoic acid?

Answer 16

SMVT

Question 17

In the transselenation pathway, a plp-dependent lyase helps generate which selenium-containing amino acid that is then incorporated into seloproteins?

Answer 17

selenocysteine (secys)

Question 18

decarboxylation

Answer 18

a reaction requiring vit b6 to synthesize neurotransmitters like dopamine and GABA

Question 19

diahrea

Answer 19

the primary side effect of consuming massive doses (10-20g) of pantothenic acid

Question 20

alcoholism

Answer 20

reduces absorption (b5)

Question 21

deamination

Answer 21

a reaction requiring vit b6 to remove an amino group so the molecule can be used for energy.

Question 22

unlike most water-soluble vitamins, vit b6 is stored extensively in the body. where is 75-80% of it stored?

Answer 22

muscle tissue

Question 23

the recommended daily intake for vit b5 for general adults?

Answer 23

5 mg/day

Question 24

what is the primary biochemical function of biotin

Answer 24

carboxylation reactions

Question 25

what is the rda for folate during pregnancy

Answer 25

600 ug/day

Question 26

what type of anemia is most commonly caused by folate deficiency?

Answer 26

megaloblastic (macrocytic) anemia

Question 27

what is the biologically active (coenzyme) form of folate in the body?

Answer 27

tetrahydrofolate (thf)

Question 28

biotin deficiency is most likely to occur because biotin absorption is inhibited by which protein

Answer 28

albumin

Question 29

a simple primary function of vit b12

Answer 29

cofactor in dna synthesis (via isomerase/mutae reactions)

Question 30

which of the following is an active form of vitamin a

Answer 30

retinol

Question 31

the BCO1 enzyme helps cut large plant derived b-carotene into smaller fragments that can later be converted into active forms of vitamin a

Answer 31

true

Question 32

RARE stands for

Answer 32

retinoic acid response element

Question 33

vit b12 is primarily absorbed in the

Answer 33

ileum

Question 34

after a-tocopherol neutralizes a lipid peroxyl radical, it becomes the a-tocopheroxyl radical. which antioxidant most directly replenishes/regenerates a-tocopherol back to its active form?

Answer 34

vit c

Question 35

which is the active (hormonal) form of vit d in the body?

Answer 35

1,25-dihydroxyvitamin D3 (calcitrol)

Question 36

in vit e, what structural feature distinguishes tocotrienols from tocopherols?

Answer 36

tocotrienols have an unsaturated side chain with three double bonds, while tocopherols have a saturated side chain.

Question 37

which vit d form is the plant and fungal version?

Answer 37

vit d2 (ergocalciferol)

Question 38

what is considered the most biologically active form of vit e in humans?

Answer 38

alpha-tocopherol

Question 39

what is the RDA for calcium in most adults aged 19-50

Answer 39

1000 mg/day

Question 40

which of the following is a major function of vit k in the body?

Answer 40

blood clotting

Question 41

which of the following INHIBITS calcium absorption

Answer 41

oxalic acid and phytic acid

Question 42

where is 99% of the body's calcium stored

Answer 42

teeth and bones

Question 43

which vit k form has the highest bioavailability and is primarily found in fermented foods like natto?

Answer 43

menaquinone 7 (MK-7)

Question 44

phosphorus absorption from plant sources is lower than from animal sources primarily because of

Answer 44

phytic acid binding

Question 45

what is a good dietary source for magnesium

Answer 45

pumpkins seeds

Question 46

declining magnesium intake over the past century is primarily attributed to increased consumption of

Answer 46

refined grains

Question 47

in bone, phosphorus is primarily found as

Answer 47

hydroxyapatite