Q&A Hero

Q: which of the following is an early sign of vitamin c deficiency? a.bleeding gums b.pernicious anemia c.appearance of a cold d.hysteria and depression

Q: how much vitamin c is needed daily to raise blood ascorbic acid concentrations to a maximum? a.10 mg b.75 mg c.125 mg d.200 mg

Q: what is the minimum daily amount of ascorbic acid that will prevent the appearance of scorbutic symptoms in human beings? a.10 mg b.30 mg c.50 mg d.60 mg

Q: which of the following vitamins is known to deactivate histamine, a substance that causes nasal congestion? a.niacin b.vitamin e c.vitamin c d.vitamin b12

Q: why might vitamin c supplements be beneficial in treating the common cold? a.they deactivate histamine b.they reduce episodes of diarrhea c.they destroy intestinal pathogens d.they alter hypothalamic control of body temperature

Q: which of the following represents the results of well-controlled studies of vitamin c supplementation on the resistance to, and recovery from, colds? a.there was a reduction in the duration of colds by 50% on the average b.there was only a minor effect on reducing the number and severity of colds c.there was a consistent reduction in the duration of colds in people who consumed at least 200 mg a day d.there was a significant reduction in the number of colds only in people who consumed more than three grams per day

Q: what organ stores the highest concentration of vitamin c? a.liver b.muscle c.thyroid gland d.adrenal glands

Q: the synthesis of collagen requires both vitamin c and a.iron b.zinc c.cobalamin d.beta-carotene

Q: the protein that requires ascorbic acid for its formation is a.keratin b.albumin c.collagen d.hydroxyproline

Q: in what capacity does vitamin c function? a.coenzyme for energy release b.cofactor in collagen formation c.cofactor with calcium in blood coagulation d.coenzyme in the formation of red blood cells

Q: which of the following is a general function of vitamin c? a.antiviral agent b.antifungal agent c.anticancer agent d.antioxidant agent

Q: what is a free radical? a.an inactive vitamin b.an unphosphorylated vitamin c.a molecule of unbound cobalamins d.a molecule with at least one unpaired electron

Q: which of the following characteristics is shared by vitamins b6, b12, c and folate? a.required for glycolysis b.consumption prevents anemia c.required in microgram quantities d.found in citrus products and legumes

Q: which of the following is an overt sign of a possible b vitamin deficiency? a.anemia b.smooth tongue c.abnormal liver function d.abnormal heart function

Q: which of the following is frequently affected by deficiencies of the b vitamins? a.bones b.tongue c.eyesight d.hair and nails

Q: which of the following is not known to be a vitamin for human beings? a.cobalamin b.ubiquinone c.pyridoxine d.pantothenic acid

Q: which of the following is not known to be required in the diet of human beings? a.folic acid b.lipoic acid c.ascorbic acid d.pantothenic acid

Q: which of the following is known to perform an essential function in the human body? a.carnitine b.orotic acid c.methoxantin d.pangamic acid

Q: which of the following nutrients is synthesized in significant amounts in the body? a.choline b.thiamine c.ascorbic acid d.pantothenic acid

Q: which of the following is a feature of choline in nutrition? a.it is an analog of ascorbic acid b.it is abundant in green leafy vegetables c.the body can synthesize it from cysteine d.average intakes in the united states are lower than recommended

Q: which of the following vitamins has an rda? a.biotin b.choline c.cobalamin d.pantothenic acid

Q: the adult rda for vitamin b12 (g/day) is a.0.5 b.1.25 c.2.4 d.4.0

Q: which of the following is a characteristic of vitamin b12 nutrition? a.toxicity symptoms are serious and irreversible b.units in food are expressed as cobalamin equivalents c.it is inactivated when the food is heated in a microwave d.bioavailable amounts are found in fermented soy products

Q: of the following foods, which would be the only source of vitamin b12? a.pecans b.hot dog c.cauliflower d.whole-grain bread

Q: why are strict vegetarians at risk of developing a vitamin b12 deficiency? a.vegetarian diets inhibit absorption of the vitamin b.vegetarian diets provide insufficient amounts of the vitamin c.the fiber content of vegetarian diets causes decreased storage by the liver d.the fiber content of vegetarian diets causes increased excretion of the vitamin

Q: which of the following is a feature of vitamin b12 bioavailability? a.synthetic b12 in supplement form is highly utilizable b.fermented soy products are optimal sources of the vitamin c.yeast consumed by vegans is a good source of the vitamin d.sea algae such as spirulina contain vitamin b12 that is about 50% available

Q: why are fermented soy products, sea algae, and most nutritional yeast products poor sources of vitamin b12? a.the vitamin is not in a bioavailable form b.these foods contain high amounts of antiintrinsic factor c.the vitamin is readily destroyed by the presence of microbes d.these foods contain high levels of folate, which inhibits b12 absorption

Q: which of the following is a feature of vitamin b12 nutrition? a.deficiencies lead to wet beriberi b.even marginal deficiency impairs cognitive function c.excess intake leads to loss of appetite and constipation d.severe deficiency is characterized chiefly by free-radical damage

Q: among the following water-soluble vitamins, a secondary deficiency would most likely be seen for a.biotin b.thiamin c.vitamin c d.vitamin b12

Q: which of the following is not known to be a risk factor for development of atrophic gastritis? a.age over 50 yrs b.iron deficiency c.helicobacter pylori infection d.avoidance of leafy vegetables

Q: pernicious anemia results from a combination of lack of intrinsic factor and a.ariboflavonosis b.lack of hydrochloric acid c.lack of pancreatic vitaminases d.pharmacologic intakes of folate

Q: in a person who loses the ability to absorb vitamin b12, approximately what period of time could elapse before deficiency signs develop? a.one month b.six months c.one year d.three years

Q: normally, the bodys storage and re-utilization of vitamin b12 prevents a primary or secondary deficiency from occurring until after about a.3 days b.3 weeks c.3 months d.3 years

Q: if a person refrained from ingesting any of the water-soluble vitamins, deficiency symptoms would appear last for a.folate b.vitamin c c.vitamin b1 d.vitamin b12

Q: which of the following is a common treatment for pernicious anemia caused by inadequate absorption? a.injection of cobalamin b.topical administration of liver extract c.oral supplements of b-vitamin complex d.a diet high in liver and green, leafy vegetables

Q: a similar type of anemia is produced when there is a deficiency of either a.riboflavin or niacin b.vitamin b12 or folate c.thiamin or riboflavin d.vitamin b6 or vitamin b12

Q: which of the following is a property of vitamin b12? a.it is efficiently recycled by the body b.it is necessary for protection from pinpoint hemorrhages c.it requires attachment to fatty acids for transport in the circulation d.it is absorbed from the stomach with the aid of a special binding protein

Q: the absorption of which of the following vitamins is most affected by the disorder atrophic gastritis? a.choline b.vitamin c c.vitamin b12 d.pantothenic acid

Q: the nasal spray route represents a safe and efficacious means for the supply of a.folate b.vitamin b1 c.vitamin c d.vitamin b12

Q: pernicious anemia results from a deficiency of a.folate b.selenium c.vitamin b12 d.iron and copper

Q: what is the most likely reason for the development of a vitamin b12 deficiency? a.inadequate intake b.increased excretion c.inadequate absorption d.increased losses in food preparation

Q: what is the function of intrinsic factor in vitamin b12 absorption? a.it catalyzes release of the vitamin from its protein-bound form b.it attaches to the vitamin, thereby allowing absorption from the small intestine c.it acts as a storage protein for the vitamin within the intestinal epithelial cells d.it acts as a cofactor for mucosal enzymes involved in absorption of the vitamin

Q: which of the following is not among the factors required for efficient dietary absorption of vitamin b12? a.pepsin b.intrinsic factor c.hydrochloric acid d.mucosal cobalaminase

Q: which of the following is required for the absorption of dietary vitamin b12? a.bile b.lipase c.intrinsic factor d.carboxypeptidase

Q: which of the following foods is highest in folate? a.meats b.starches c.dairy products d.green, leafy vegetables

Q: what is the adult rda for folate (g/day)? a.100 b.200 c.400 d.800

Q: what is the rda for folate for a woman weighing 132 pounds? a.180 g/day b.220 g/day c.242 g/day d.400 g/day

Q: among all the vitamins, which is believed to be most vulnerable to interactions with drugs? a.folate b.niacin c.vitamin b6 d.vitamin b12

Q: folate deficiency has been reported in infants fed a.soy milk b.goats milk c.chicken liver d.infant formula

Q: which of the following is associated with a deficiency of folate? a.hemolysis b.hypoxemia c.hemolytic anemia d.macrocytic anemia

Q: physiological stresses such as blood loss, burns, measles, and cancer are known particularly to increase the risk of deficiency for a.biotin b.folate c.riboflavin d.pantothenic acid

Q: which of the following is known to significantly affect the bodys folate status? a.sedentary lifestyle b.some anticancer drugs c.excess protein intake d.insufficient fiber intake

Q: which of the following is representative of folate availability in foods? a.good sources are dairy products and meats b.poor sources are fruit juices and vegetable juices c.much of the vitamin is lost due to heat and oxidation d.only about 10% of the amount in foods is bioavailable

Q: which of the following substances is known to adversely affect folate utilization? a.insulin b.calcium supplements c.regular use of antacids d.vitamin b12 supplements

Q: what vitamin is involved mainly with the replacement of red blood cells and digestive tract cells? a.folate b.niacin c.thiamin d.riboflavin

Q: the appearance of vitamin b12 deficiency symptoms may be delayed due to high intake of supplements of a.folate b.niacin c.vitamin c d.vitamin b6

Q: a deficiency of which of the following vitamins results in accumulation of homocysteine in the blood? a.folate b.biotin c.niacin d.vitamin k

Q: because of adverse interactions with other vitamins, a safe daily folate intake is up to a.400 g b.600 g c.1,000 g d.2,000 g

Q: nicole is pregnant and is trying to monitor her folate intake. she is eating foods high in folate as well as taking folate supplements, and she is having a hard time determining how many dietary folate equivalents she is consuming. below is a list of her daily intake with respect to folate: 1/2 cup of cooked lentils (180 g food folate) 1/2 cup of fresh orange juice (60 g food folate) folate supplement (200 g) how many dfes is nicole consuming? a.440 b.480 c.540 d.580

Q: by law, what amount of folate (g) must be added to 100 g of food products such as breads, flour, and rice? a.0 b.5 c.50 d.140

Q: which of the following is a feature of folate nutrition? a.the coenzyme form is fad b.dairy foods are a poor source of folate except for goats milk c.insufficient folate intake results in deficiency of homocysteine d.synthetic folate is 70% more available than naturally occurring food folate

Q: what vitamin contains cobalt? a.a b.b6 c.b12 d.pantothenic acid

Q: methylcobalamin is a coenzyme form of a.vitamin b1 b.vitamin b6 c.vitamin b12 d.niacin

Q: which of the following is true regarding b vitamins and homocysteine metabolism? a.folate catabolyzes homocysteine b.biotin supplements reduce blood homocysteine levels c.excessive homocysteine intake reduces vitamin b12 absorption d.high blood homocysteine levels correlate with reduced incidence of colon cancer

Q: which of the following is a type of neural tube defect? a.scurvy b.beriberi c.pellagra d.spina bifida

Q: research has shown that the risk for neural tube defects is lowered by taking supplements of a.niacin b.folate c.vitamin c d.vitamin b12

Q: how many dietary folate equivalents are provided by 100 g of a folate supplement? a.50 b.70 c.133 d.170

Q: the percent bioavailability of a folate supplement taken on an empty stomach is a.5 b.25 c.50 d.100

Q: approximately what percentage of naturally occurring dietary folate is bioavailable? a.10 b.25 c.50 d.80

Q: what is the most likely explanation for the impaired functioning of the gi tract resulting from folate deficiency? a.insufficient bile production, thereby promoting fat malabsorption and diarrhea b.reduced mucosal cell replacement, thereby resulting in decreased gi functioning c.decreased enzymatic capacity in the intestines, thereby resulting in malabsorption d.decreased oxygen supply to body tissues, with the intestines being particularly affected because of their high metabolic activity

Q: which of the following is not a feature of folate nutrition? a.most food folate is bound to a string of amino acids b.folate is actively secreted back into the gi tract with bile c.food folate must be hydrolyzed by intestinal cell enzymes prior to absorption d.folate must be methylated by homocysteine prior to crossing the brush border membrane

Q: a person with a disorder that limits absorption of bile is at increased risk for deficiency of a.folate b.niacin c.riboflavin d.ascorbic acid

Q: which of the following vitamins is usually found in a form that is bound to one or more glutamic acid molecules in food? a.folate b.thiamin c.vitamin b6 d.ascorbic acid

Q: which of the following vitamins undergoes significant enterohepatic circulation? a.folate b.niacin c.thiamin d.pyridoxine

Q: which of the following characteristics is shared by vitamin b12 and folate? a.both are required for nucleic acid synthesis b.both require intrinsic factors for their release from food proteins c.both are found in significant amounts in green leafy vegetables d.both are considered problem nutrients for strict vegetarians

Q: which of the following is not among the properties of folate in nutrition? a.it is needed for proper functioning of vitamin b12 b.it functions primarily in the transfer of amino groups c.the coenzyme of folate requires vitamin b12 to function properly d.it requires enzymes on the intestinal mucosa to enhance its absorption from most foods

Q: pteroylglutamic acid is known as a.folate b.choline c.inositol d.pyridoxamine

Q: which of the following is an essential dietary nutrient for human beings? a.folate b.inositol c.methoxatin d.lipoic acid

Q: on a per-kcalorie basis, which of the following foods is richest in vitamin b6? a.meats b.fruits c.legumes d.grains

Q: what is the adult rda for vitamin b6? a.1.3 mg/day b.5.5 mg/day c.15 mg/day d.22 mg/day