ndfs 200 test 5

Question 1

riboflavin deficiency

Answer 1

aribinoflavinosis: inflamed tongue, mouth, and throat and develops 2 months after initial deficiency

at risk: alcoholics, malabsorption disorders, poor diets

Question 2

niacin

Answer 2

Vitamin B3
2 forms: nicotinic acid and nicotinamide
NADH and NADPH

Question 3

niacin sources

Answer 3

food, synthesized from tryptophan
RDA: 16 mg/day for men and 14 mg/day for women

Question 4

niacin absorption

Answer 4

-absorbed in stomach a little and in small intestine by active transport and passive diffusion
-free niacin is low in corn–must be treated with lye
-stored in liver

Question 5

niacin functions

Answer 5

energy metabolism, anabolic pathways use NADPH

Question 6

niacin deficiency

Answer 6

pellagra: dermatitis, diarrhea, dementia
widespread damage

Question 7

pantothenic acid

Answer 7

CoA as acyl carrier at -SH end
abundant in foods, deficiency rare
AI based on intake adequate to replace urinary excretion (5mg/day)

Question 8

pantothenic acid functions

Answer 8

acetyl CoA formation from pyruvate, beta oxidation, amino acids, alcohol
-initiate CAC and fatty acid synthesis

Question 9

biotin

Answer 9

-humans excrete more than we consume because gut bacteria synthesizes it
-can be free or covalently linked to lysine

Question 10

biotin pt 2

Answer 10

AI 30 ug/day, absorbed by sodium dependent channel, excreted in urine and bile

Question 11

biotin deficiency

Answer 11

due to rare genetic disease, lack biotinidase

Question 12

biotin functions

Answer 12

carboxylation reactions
–pyruvate to oxaloacetate
–fatty acid synthesis
–catabolism of amino acids

Question 13

vitamin B6

Answer 13

3 forms: can be phosphorylated and activated
-stored in muscle
-RDA 1.7 mg/day for men and 1.5 mg/day for women
-UL: 100 mg, can cause nerve damage (most toxic of all water soluble vitamins)

Question 14

vitamin B6 functions

Answer 14

enzymatic reactions
metabolism
–amino acids (transamination)
–without vitamin B6 all amino acids would be essential
synthesis of compounds
–heme synthesis
–neurotransmitters

Question 15

vitamin B6 deficiency

Answer 15

microcytic anemia, convulsions, depressions, confusions
at risk: blacks, smokers, alcoholics, oral contraceptives

Question 16

vitamin B6 pharmacological uses

Answer 16

carpal tunnel syndrome, premenstrual syndrome, nausea during pregnancy

Question 17

folate absorption

Answer 17

polyglutamates are cleaved, monoglutamate is absorbed through active transport