Most vitamins are required daily in___________amounts
C) milligram and microgram
Water-soluble vitamin
B) are less likely to produce symptoms of toxicity than are fat-soluble vitamins
LIst the standard names of the water-soluble vitamins
-thiamin
-riboflavin
-niacin
-vitamin B-6
-folate
-vitamin B-12
-pantothenic acid
-biotin
-vitamin C
True/False (support your answer with an explanation)
Bioavailability refers to the amount of a vitamin or minerals that a food contains
False
Bioavailability refers to the amount of a vitamin or mineral that the body actually absorbs and uses
Thiamin pyrophosphate (TPP)
D) is the coenzyme form of thiamin
True/False (support your answer with an explanation)
Because atheletes engage in much vigourous exercise they require supplement of thiamin
False
Adequate thiamin may be obtained on a regular diet. provided the diet is adequate in energy and nutritious food
Large doses of thiamin cause
D) non of the above
An early clinical sign of mild thiamin deficiency is
C) loss of appetite
Of the foods listed below,____________is the best source of thiamin
B) a 90 gram (three ounce) pork chop
The food group that makes the most substantial contribution to daily thiamin intake is
C) grain products
Of the procedures listed below,____________would have the greatest effect on the thiamin in food
A) adding baking soda to baked beans to speed up the cooking time
The major function of FAD and FMN is as carriers if
C) hydrogen atoms
Riboflavin deficiency
A) may be marginally present in people abusing alcohol
Riboflavin deficiency is clinically manifested by
D) inflammation of mucous membranes
Riboflavin is easily destroyed by
C) ultraviolet light
The food group making the most substantial contribution to daily riboflavin intake is
C) milk products
The abbreviations for the two enzyme forms of niacin are _________and________
-NAD
-NADP
Niacin is not recognized as
D) necessart for hemoglobin synthesis
Pellagra develops if diets
C) are low in tryptophan and performed niacin
Niacin defiency affects primarily the
B) skin and central nervous system
A diet that contains one milligram of preformed niacin and 240 mg of excess tryptophan has_________niacin equivalents (NE)
A) 5
Large doses of niacin may have therapeutic value in
C) lowering blood cholesterol levels
The food group making the most substantial contribution to daily niacin intake is
A) meat and alternatives
The primary role of vitamin B-6 is in
A) protein metabolism
The only specific symptom reflecting vitamin B-6 deficiency is
C) microcytic anemia
Of the foods listed below,___________is the best source of vitamin B-6
C) a medium banana
Vitamin B-6 is not sensitive to
B) cabon dioxide
The abbreviation for the primary coenzyme form of folate is_________
-THF
Most of the folate present in foods is
C) tetrahydrofolate
The main function of folate is as a carrier of
C) oxygen
Symptoms of folate deficiency include
A) macrocytic anemia
True/False (support your answer with an explanation)
The behavioural changes of depression, mental confusion, and abnormal nerve reflexes are the result of irreversible nerve damage resulting from folate deficiency
False
These neurological symptoms are related to teh concentration of neurotransmitters in the brain and nervous system. They can be reversed once sufficient folate is available
Folate is
B) found in highest quantities in green, leafy plants
During pregnancy, folate requirement is increased because
D) cell division and cell growth are increased
Of the foods listed below,__________contains the most folate
C) half a cup of cooked lentils
Vitamins B-12 does not function in
C) production of gastric hydrochloric acid
The intrinsic factor aids in vitamin B-12 absorption by
D) attaching the vitamin to receptor sites on mucosal cells in the ileum
Inherited pernicious anemia can be prevented by
B) intramuscular injections of vitamin B-12
Vitamin B-12 requirements can easily be met if
B) foods of animal origin are consumed
Strict vegans may become deficient in vitamin B-12 because
A) they do not eat animal products
True/False (support your answer with an explanation)
Since folate and B-12 have similar roles in nerve functioning, high folate intakes can reverse the symptoms of peripheral nerve degeneration in vitamin B-12 deficiency
False
High intakes of folate can reverse the symptom of megaloblastic anemia in vitamin B-12 deficiency, but cannot reverse peripheral nerve degeneration. Unlike the insufficiency of neurotransmitters caused by of folate deficiency, irreversible nerve damage results from demyelination of nerve fibres during vitamin B-12 deficiency
Vitamin C does not act as an antiooxidant by
A) donating hydroxyl groups
A structural protein that requires vitamin C for its formation is
A) collagen
Vitamin C assists iron absorption by
C) reducing ferric iron to ferrous iron
An early sign of scurvy is
B) pinpoint hemorrhages
Wound healing may be impaired in an individual with vitamin C deficiency because
C) collagen synthesis is impaired
Of the functions listed below, only________is not a role of vitamin C in the body
D) aiding vitamin B-12 absorption
A possible side effect of large intakes of vitamin C is
A) kidney stones
True/False (support your answer with an explanation)
Rebound scurvy is the re-occurence of vitamin C deficiency
False
Rebound scurvy occurs when high vitamin C intake is suddenly stopped. Since the body has been conditioned to a high intake of vitamin C, the normal intake in insufficient to prevent deficiency
The RDA for vitamin C in cigarette smokers is higher because
B) there is increased oxidative stress due to cigarette smoke
Of the conditions listed below, only________would not result in an increased vitamin C requirement
A) obesity
Of the foods listed below, only____________is not a rich source of vitamin C
D) a medium pear
Of the foods listed below,___________would probably contain the most vitamin C
A) raw broccoli
True/False (support your answer with an explanation)
Vitamin C does not prevent or cure the common cold, but it may shorten the duration of a cold to a small extent
Vitamin C prevents the formation of a group of carcinogens called
