;Advanced Nutrition/Human
Metabolism Exam
With answers
60 mg of tryptophan equals how many nitrogen equivalents (NEs) - answer-1 mg
NE
1 gram of complete protein equals how many mg of tryptophan - answer-10 mg
tryptophan
What two ways does vitamin C enhance the absorption of nonheme iron? -
answer-1. reduces iron from a ferric state (Fe3+) to a ferrous state (Fe2+)
2. forms a soluble complex w/ the reduced iron in the alkaline pH of the small
intestine
What is the formula for calculating dietary folate equivalents (DFEs) - answer-DFE
= micrograms of food folate + (1.7 x micrograms folic acid)
Major food sources for vitamin B1 (thiamin) - answer-Animal meats (especially
pork), salmon, legumes, whole and enriched grains, yeast, wheat germ and soy
milk
Major food sources for vitamin B2 (riboflavin) - answer-Dairy products (milk,
yogurt, cheese), eggs, animal meats, legumes, green vegetables (spinach)
Major food sources for vitamin B3 (niacin) - answer-Beef, pork, fish, poultry,
whole and enriched grains, fortified cereals, seeds and legumes (also in coffee
and tea)
Major food sources for vitamin B5 (pantothenic acid) - answer-Found everywhere
(pantos) but good sources are animal meats, egg yolk, yogurt, legumes, whole
grain cereals, potatoes, mushrooms and avocados
Major food sources of vitamin B7
(biotin) - answer-Beef liver, soy beans and egg yolk.
Major food sources of vitamin B9
(folate) - answer-Mushrooms, spinach, broccoli, asparagus, Brussels sprouts,
turnips, collard greens, okra, legumes, strawberries and oranges and liver
, Major food sources of folic acid - answer-Fortified cereals, breads and grain
products
Major food sources of vitamin B12 (cobalamin) - answer-Meat and meat products,
fortified cereals and soy milk.
None of the water soluble vitamins are stored in the body except for which one? -
answer-Vitamin B12 & B6
All of the water soluble vitamins are absorbed via active diffusion (except in high
concentrations = passive) except for which one? - answer-Vitamin B6
Which two ways are water soluble vitamins found in the blood stream? - answer-
Free form or with a protein transporter (albumin)
Which water soluble vitamins are not associated w/ a deficiency disease? -
answer-Biotin, pantothenic acid, vitamin B6 and riboflavin
Which of the water soluble vitamins have a UL? - answer-Vitamin C, vitamin B6,
niacin and folate
Vitamin C functions? - answer-Antioxidant; and hydroxylating reactions involved
in the synthesis of collagen, carnitine, tyrosine and neurotransmitters
(norepinephrine and serotonin)
Vitamin C in synthesis of collagen. What is the mechanism of action? - answer-3
hydroxylation reactions are required. Relates to the iron cofactor - the iron
cofactor in the enzymes is oxidized during the prolyl (3- and 4-) and lysyl
hydroxylase reactions and vitamin C functions as the reductant, reducing iron
back to the ferrous (2+) state
Vitamin C in synthesis of carnitine. What is the mechanism of action? - answer-2
hydroxylation reactions. Vitamin C functions as a reducing agent, reducing the
iron atom from the ferric state (Fe3+) back to the ferrous state (2+) for the
reactions catalyzed by trimethyllysine hydroxylase and 4-butyrobetaine
hydroxylase.
Vitamin C in synthesis of tyrosine. What is the mechanism of action? - answer-
Regenerates tetrahydrobiopterin (co-substrate for hydroxylation of phenylalanine
by the iron-dependent enzyme phenylalanine hydroxylase)
Metabolism Exam
With answers
60 mg of tryptophan equals how many nitrogen equivalents (NEs) - answer-1 mg
NE
1 gram of complete protein equals how many mg of tryptophan - answer-10 mg
tryptophan
What two ways does vitamin C enhance the absorption of nonheme iron? -
answer-1. reduces iron from a ferric state (Fe3+) to a ferrous state (Fe2+)
2. forms a soluble complex w/ the reduced iron in the alkaline pH of the small
intestine
What is the formula for calculating dietary folate equivalents (DFEs) - answer-DFE
= micrograms of food folate + (1.7 x micrograms folic acid)
Major food sources for vitamin B1 (thiamin) - answer-Animal meats (especially
pork), salmon, legumes, whole and enriched grains, yeast, wheat germ and soy
milk
Major food sources for vitamin B2 (riboflavin) - answer-Dairy products (milk,
yogurt, cheese), eggs, animal meats, legumes, green vegetables (spinach)
Major food sources for vitamin B3 (niacin) - answer-Beef, pork, fish, poultry,
whole and enriched grains, fortified cereals, seeds and legumes (also in coffee
and tea)
Major food sources for vitamin B5 (pantothenic acid) - answer-Found everywhere
(pantos) but good sources are animal meats, egg yolk, yogurt, legumes, whole
grain cereals, potatoes, mushrooms and avocados
Major food sources of vitamin B7
(biotin) - answer-Beef liver, soy beans and egg yolk.
Major food sources of vitamin B9
(folate) - answer-Mushrooms, spinach, broccoli, asparagus, Brussels sprouts,
turnips, collard greens, okra, legumes, strawberries and oranges and liver
, Major food sources of folic acid - answer-Fortified cereals, breads and grain
products
Major food sources of vitamin B12 (cobalamin) - answer-Meat and meat products,
fortified cereals and soy milk.
None of the water soluble vitamins are stored in the body except for which one? -
answer-Vitamin B12 & B6
All of the water soluble vitamins are absorbed via active diffusion (except in high
concentrations = passive) except for which one? - answer-Vitamin B6
Which two ways are water soluble vitamins found in the blood stream? - answer-
Free form or with a protein transporter (albumin)
Which water soluble vitamins are not associated w/ a deficiency disease? -
answer-Biotin, pantothenic acid, vitamin B6 and riboflavin
Which of the water soluble vitamins have a UL? - answer-Vitamin C, vitamin B6,
niacin and folate
Vitamin C functions? - answer-Antioxidant; and hydroxylating reactions involved
in the synthesis of collagen, carnitine, tyrosine and neurotransmitters
(norepinephrine and serotonin)
Vitamin C in synthesis of collagen. What is the mechanism of action? - answer-3
hydroxylation reactions are required. Relates to the iron cofactor - the iron
cofactor in the enzymes is oxidized during the prolyl (3- and 4-) and lysyl
hydroxylase reactions and vitamin C functions as the reductant, reducing iron
back to the ferrous (2+) state
Vitamin C in synthesis of carnitine. What is the mechanism of action? - answer-2
hydroxylation reactions. Vitamin C functions as a reducing agent, reducing the
iron atom from the ferric state (Fe3+) back to the ferrous state (2+) for the
reactions catalyzed by trimethyllysine hydroxylase and 4-butyrobetaine
hydroxylase.
Vitamin C in synthesis of tyrosine. What is the mechanism of action? - answer-
Regenerates tetrahydrobiopterin (co-substrate for hydroxylation of phenylalanine
by the iron-dependent enzyme phenylalanine hydroxylase)
