Test
Exam 5 - Vitamins CH 9 & 10
Este test tiene tipos de pregunta que se abren en el reproductor de siempre.
Preguntas del test (133)
1When water-soluble vitamins are consumed in excess of body needs, generally the excess is:
- Aexcreted in the feces
- Bstored in liver, bone and adipose tissue
- Cexcreted in urine
- Dnot absorbed
2A major function of B vitamins is to serve as:
- Aantibodies
- Benergy source
- Cpart of a coenzyme
- Delectrolytes
3Most animals synthesize their own ascorbic acid from _____.
- Aglucose
- Bglutamine
- Cglycogen
- Dalanine
4When ascorbic acid becomes dehydroascorbic acid it has _____.
- Alost 2 e-
- Blost 1 e-
- Cgained 2 e-
- Dgained 1 e-
5Vitamin C acts as a cofactor by maintaining iron in a reduced state in:
- Acollagen synthesis
- Bmethylation of homocysteine
- Crelease of energy from nutrients
- Dred blood cell synthesis
6Although excess absorbed ascorbic acid is excreted in urine, the body has an estimated maximal body pool of about _____, which can be maintained with intakes of 100-200 mg vitamin C per day.
- A500 mg
- B1000 mg
- C1500 mg
- D2000 mg
7Which water-soluble vitamin contributes to “intracellular cement” in the formation of scar tissue and wound healing?
- Athiamin
- Briboflavin
- Cvitamin C
- Dvitamin B12
8Which of the following molecules synthesized with the help of vitamin C underscores the importance of vitamin C to fat metabolism?
- Acarnitine
- Bcollagen
- Ctyrosine
- Dnorephinephrine
9Ascorbic acid provides a reducing equivalent so that iron is in the _____ form in lysyl hydroxylase.
- Aferric
- Bferrous
10Without enough vitamin C, collagen would ____
- Abe too tightly coiled
- Bbe over-hydroxylated
- Cbe under-hydroxylated
- Dtoo strong and less flexible
11A primary function of vitamin C is to act as an:
- Aantiviral agent
- Bantioxidant
- Cantirachitic agent
- Dacyl transferase
12Vitamin C’s actual participation in biochemical reactions usually involves its antioxidant ability. Choose the description of this activity.
- ADonates an e- to oxidize a mineral cofactor
- BAccepts an e- to reduce a mineral cofactor
- CDonates an e- to reduce a mineral cofactor
- DAccepts an e- from the quinone form of vitamin E
13The necessity of ascorbic acid for its role in _____ is believed to be the reason that people with scurvy have no energy and are very tired.
- Acollagen synthesis
- Bcreatine synthesis
- Chormone activation
- Dcarnitine synthesis
14Ascorbic acid may act as a pro-oxidant by:
- Areducing ferrous iron
- Bmobilizing ferric iron from storage
- Creacting with transferrin-bound iron
- Dreducing dehydroascorbic acid
15A major role for thiamin is:
- Aenergy transformation
- Bblood coagulation
- Ccollagen formation
- Derythrocyte synthesis
16Thiamin is important to fatty acid synthesis due to its requirement as a coenzyme for the pentose phosphate pathway enzyme _____.
- Adopamine monooxygenase
- Btransketolase
- Calpha-ketoglutarate dehydrogenase
- Dphenylalanine hydroxylase
17A consequence of thiamin deficiency is:
- Apellagra
- Bmegaloblastic anemia
- Cberiberi
- Drickets
18Erythrocyte transketolase activity is an assay to assess the status of:
- Athiamin
- BB6
- Criboflavin
- DB12
19The most common tests of thiamin status include all the following EXCEPT
- Astatic tests of urinary thiamin metabolites
- Ba static test of serum thiamin
- Can in vitro functional test of RBC enzyme
- Din vivo functional tests
20When the diet is adequate in protein, the body can synthesize niacin from which amino acid?
- Aphenylalanine
- Bvaline
- Ctyrosine
- Dtryptophan
21Which vitamin has a reduced coenzyme form important for fatty acid and cholesterol synthesis that is a product of the pentose phosphate pathway?
- Aniacin
- Bthiamin
- Criboflavin
- Dvitamin C
22Which classical vitamin deficiency is known for the four Ds: dermatitis, dementia, diarrhea, and death?
- Athiamin
- Bniacin
- Cbiotin
- Dfolic acid
23Which three vitamins are involved in the synthesis of fatty acids?
- Abiotin, vit D, thiamin
- Bthiamin, riboflavin, niacin
- Cniacin , biotin, pantothenic acid
- Driboflavin, B12, folate
24Biotin must be covalently bound to each of four different enzymes in order for them to carry out _____.
- Adecarboxylations
- Boxidation-reduction reactions
- Ctransfer of acetate groups
- Dcarboxylations
25A deficiency of what vitamin is associated with these symptoms: hallucinations, lethargy, skin rash, alopecia, and muscle pain?
- Abiotin
- Bthiamin
- Cvit C
- Dvit B12
26Folate in foods can only be absorbed in the monoglutamate form; therefore, digestive enzymes called _____ are important for folate nutriture.
- Ahydrolases
- Blipases
- Cconjugases
- Dlegumes
27To absorb folate consumed from green, leafy vegetables, _____.
- Aphosphate groups must be removed by the action of alkaline phosphatase
- Bglutamate must be transaminated to form alpha-ketoglutarate
- Cglutamic acid molecules must be removed
- Dglutamic acid molecules must be added
28Carbon in the one-carbon pool can be in the 5-methyl-THF form or the 5,10-methylene-THF form. Which statement is FALSE?
- ABoth forms of carbon can be used directly for thymidylate synthesis
- Bthe methylene group of 5,10 methylene THF can be oxidized to generate 5-methyl-THF and vice versa
- CB12 is a cofactor for utilization of the methyl group in the conversion of homocysteine to methionine
- DMore than one is false
29Which of the following reflects long-term folate status?
- Aserum folate
- Bred blood cell folate
- Chomocysteine concentration in blood
- Dserum methylmalonic acid
30The degradation of _____ provides the majority of one-carbon groups for pyrimidine synthesis. In this process _____ is formed.
- Amethionine; tetrahydrofolate
- Bserine; 5,10-methylene tetrahydrofolate
- Curidine; tetrahydrofolate
- Dhomocysteine; 5-methyl tetrahydrofolate
31In the enzyme methionine synthase, vitamin B12 acts by accepting a _____ group from _____ and donating this group to _____ to form methionine.
- Acarbon; methionine; folate
- Bmethyl; 5-methyltetrahydrofolate; homocysteine
- Cmethyl; formiminoglutamin acid; succinyl-CoA
- Dcarbon; serine; glycine
32Which is NOT a fate of homocysteine in the cell?
- Amethylated to methionine
- Bused to restore tetrahydrofolate
- Cused to synthesize cysteine
- Dused in the synthesis of leucine
335-methyl THF requires the action of which vitamin in order to form THF?
- AB12
- BB2
- Cniacin
- DC
34Elevated homocysteine levels can be due to all the following EXCEPT:
- Alow ascorbic acid
- Blow folacin
- Clow cobalamin
- Dlow pyridoxine
35Methionine is used to synthesize S-adenosylmethionine (SAM). Why is this important?
- Aso that 5-methyl THF is formed
- Bso the dUMP is catalyzed to dTMP
- Cso that fatty acids with an odd-numbered chain can be metabolized
- Dso that methyl groups are available
36Folate is vitally important for dividing cells during growth and cancer because of its essential role in the synthesis of _____.
- Alipid bilayers
- Bmitochondria
- Clysosome and perioxsomes
- Dpurines and pyrimidines
37Tetrahydrofolate is vitally important for dividing cells during growth and cancer and knowledge of this need is used in cancer treatment by giving the drug methotrexate to inhibit the enzyme _____.
- Afolylpolyglutamate synthetase
- Bdihydrofolate reductase
- Cformimino glutamate
- Dconjugase
38Which of the following would you find under B12-deficient conditions and the methyl trap hypothesis?
- Aaccumulation of 5-methylene thF
- Bdepletion of homocysteine
- Caccumulation of THF
- Daccumulation of 5-methyl THF
39What amount of supplemental folic acid is recommended daily for women of childbearing age in the United States?
- A200 ug DFE
- B400 ug DFE
- C600 ug DFE
- D800 ug DFE
40Intrinsic factor is required for the majority of absorption of which vitamin?
- AC
- BB6
- CB12
- DB2
41Vitamin B12 is absorbed in the _____.
- Aduodenum
- Bjejenum
- Cileum
- Dcolon
42The normal digestion and absorption of cobalamin requires adequate protein digestion in the stomach; the presence of 2 nonenzymatic proteins: _____; and a receptor located in the _____.
- AR binders and HCl; colon
- Bpepsin and HCl; ileum
- CR protein and intrinsic factors; ileum
- DR protein and intrinsic factor, duodenum
43Which of the water-soluble vitamins is able to be stored and retained in the body for long periods of time?
- Afolic acid
- Bniacin
- Cthiamin
- DB12
44Large amounts of folic acid can mask a vitamin B12 deficiency and prevent _____ from resulting. Over time the symptoms unique to a vitamin B12 deficiency will occur, and these are related to the _____.
- Amicrocytic anemia; muscular system
- BDNA and RNA synthesis; vascular system
- Cone-carbon transfer; nervous system
- Dmacrocytic anemia; nervous system
45Which vitamin is most involved in amino acid metabolism
- Abiotin
- Bvit E
- Cvit A
- Dvit B6
46Metabolism of vitamin B6 to the primary coenzyme form, pyridoxal phosphate, requires the action of what other B vitamin?
- AGSH
- BNAD
- CTHF
- DFMN
47A good source of vitamin B6 is muscle meats because PLP is predominantly bound to the enzyme _____.
- Aalanine amino transferase
- Bcystathionine synthase
- Cglycogen phosphorylase
- Daspartic amniotransferase
48Vitamin B6 functions importantly in all of the following EXCEPT _____.
- Atransamination of amino acids
- Bsynthesis of fatty acids
- Csynthesis of niacin
- Dglycogen breakdown
49Because vitamin B6 is involved in heme synthesis, a deficiency symptom is
- Ahypochormic, microcytic anemia
- Bseizures
- Chyperhomocysteinemia
- Dimpaired Ca metabolism
50B6-dependent transamination reactions are important in which process?
- Aglyconeogensis
- Bgluconeogenesis
- Cheme synthesis
- Dmore than one of the above
51PLP functions as a coenzyme for _____ when alanine enters the liver. Alanine becomes its α-keto acid, _____.
- Atransamination, pyruvic acid
- Btransamination, alpha-ketoglutaric acid
- Ctransmethylation, histidine
- Ddesulfation, methionine
52Pellagra symptoms may appear during B6 deficiency, because this vitamin is required in the process of obtaining niacin from tryptophan
- AVerdadero
- BFalso
53Water-soluble vitamins are not stored, but readily excreted—the one exception is that we can store folate in the liver.
- AVerdadero
- BFalso
54Pernicious anemia can be due to folate or B12 deficiency
- AVerdadero
- BFalso
55The active form of a vitamin is usually the form that has the greatest bioavailability.
- AVerdadero
- BFalso
56The primary role of vitamin C is as a reducing agent, particularly for the mineral component of a number of enzymes that becomes oxidized following catalysis of a reaction.
- AVerdadero
- BFalso
57High circulating levels of homocysteine (i.e., hyperhomocysteinemia) have been implicated in a number of pathologies including cardiovascular disease.
- AVerdadero
- BFalso
58The reason we use equivalents when discussing the RDA for some vitamins is that there are different forms of the vitamin that, by weight, are not equal in terms of vitamin activity—this is due to differences in absorption and/or metabolism.
- AVerdadero
- BFalso
59Circulating concentrations of a vitamin typically reflect diet, whereas intracellular (e.g., RBCs, leukocytes) concentrations reflect body pools.
- AVerdadero
- BFalso
60Urinary excretion of xanthurenic acid may be an indication of niacin deficiency.
- AVerdadero
- BFalso
61Biotin and B12 are both required for the synthesis of odd-chain fatty acids
- AVerdadero
- BFalso
62In the folate-dependent one-carbon pool, a carbon unit in the methyl form (i.e., 5-methyl THF) is used in the conversion of homocysteine to methionine, whereas a carbon unit in the methylene form (i.e., 5,10-methylene THF) is used in DNA synthesis.
- AVerdadero
- BFalso
63Vitamin C is a good reducing agent, meaning it keeps things reduced by undergoing irreversible oxidation; thus, it must continuously be replaced by dietary sources.
- AVerdadero
- BFalso
64Which of the carotenoid pigments has the greatest vitamin A activity?
- Aalpha-carotene
- Bbeta-carotene
- Cgamma-carotene
- Ddelta-carotene
65Choose the food that is high in vitamin A palmitate.
- Aspinach
- Bliver
- Ccarrots
- Dpumpkin
66Formation of retinol from beta-carotene requires the presence of what B vitamin?
- Aascorbic acid
- Bfolic acid
- Cniacin
- Dpyridoxal phosphate
67What happens to retinal in the enterocyte?
- Ais it esterified
- Bit is reduced to retinol
- Cit is transported into the portal blood
- D15, 15' dioxygenase acts to form beta-carotene
68Choose the ONE correct statement.
- ABeta-carotene is hydrolyzed in the jejunum before it is absorbed
- BRetinol does not need to form a micelle to cross the USW
- CBeta-carotene dioxygenase activity occurs in the lumen of the ileum
- DRetinol must be re-esterified to be carried in the chylomicron
69In order to be carried in the chylomicron, retinol (once in the enterocyte) is _____.
- Aesterified by lecithin retionol acyl transferase
- Bconverted to retinaldehyde by retinaldehyde reductase
- Cattached to a VLDL
- Dattached to an RXR reveptor on the nucles
70The majority of vitamin A is stored in the liver, while carotenoids are stored mainly in the _____ tissue.
- Amuscle
- Beye
- Cadipose
- Dskin
71In what cells will you find most of the retinol and vitamin A stored?
- Astellate
- Bgallbladder
- Cfundus
- Dantrum
72How will retinol, once secreted from the liver, be found in the blood?
- Aattached to RBP and transtheyretin
- Battached to albumin
- Cattached to chylomicron
- Dattached to RBO and stellate cells
73Which of the following is needed for the visual cycle?
- A11-cis retinal
- B9-cis retinoic acid
- Clycopene
- Dcryptoxanthin
74Vitamin A functions in the visual cycle. This mechanism involves a vitamin A molecule called [blank_start]11-cis retinal[blank_end], combining with [blank_start]opsin[blank_end] to form [blank_start]rhodopsin[blank_end]. When photon energy strikes this molecule, it splits and causes a conformational change in the molecule, causing an electrical signal to be sent to the brain.
- A11-cis retinal
- Ball-trans retinal
- Copsin
- Dretinol
- Erhodopsin
- Fretinoic acid
75Within the nucleus, all trans-retinoic acid and/or 9-cis retinoic acid binds to _____.
- Anuclear retinoic acid receptors
- Bmannosylated glycoproteins
- Ccell aggregates
- Dtranscription factors
76Why is retinoic acid considered a hormone?
- Ait has receptors on the nucleus and causes a change in protein synthesis
- Bit has biologic function similar to insulin
- Cit is synthesized in the same tissue that it affects
- Dit causes the catabolism (break down) of body proteins
77Which vitamin directs cellular differentiation of epithelial cells?
- Ariboflavin
- Bvit K
- Cvit E
- Dvit A
78Where would you find retinoid X receptors (RXR)?
- Acytosol
- Bnucleus
- Cmitochondria
- Dnone of the above
79Which vitamin is said to be essential for growth and immune system function?
- AK
- BA
- CD
- DE
80Which is NOT related to the functions of vitamin A?
- Aneurological function
- Bgrowth
- Cimmunity
- Dcell differentiation
81Choose the correct statement about the quenching of singlet oxygen by carotenoids.
- Acarotenoids donate an electron to the singlet oxygen to make it stable
- Bcarotenoids covalently bond with the singlet oxygen to make it stable
- Ccarotenoids donate energy so that the excited electron returns to it's orbital
- Dcarotenoids absorb the extra energy that is held by the singlet oxygen
82Which is the strongest antioxidant?
- Abeta-carotene
- Balpha-tocopherol
- Cbeta-cryptoxanthin
- Dlycopene
83Would you recommend β-carotene supplementation to a smoker to decrease risk to lung cancer?
- AYes - beta-carotene can quench singlet oxygen
- Byes - smoking increases free radical formation; beta carotene can decrease free radicals
- Cno- beta carotene supplements may be harmful to smokers and their use is not advised for the general public
- Dno beta-carotene supplements can cause a vitamin A toxicity and liver cirrhosis
84Choose the phrase which best explains the following statement: “β-carotene is no magic bullet.”
- AIt doesn't decrease the reactivity of singlet oxygen molecules
- Bit is not the only health-promoting molecule in fruits and veggies
- CSupplements of it cannot be manufactured cheaply enough
- DIt can not replace vit E in terminating the auto-oxidation of fatty acids
85Which micromineral deficiency interferes with vitamin A metabolism by reducing retinol-binding protein?
- Amanganese
- Bzinc
- Cselenium
- Diron
86Which symptom of a vitamin A deficiency is most likely responsible for deficiency-related deaths?
- Aits function as a teratogen
- Bpoor cellular differentiation and growth
- Ckeratinization of the cornea
- Dsevere infections
87An individual with poor vitamin A status would have a _____ RDR than someone with a good vitamin A status.
- Agreater
- Blesser
88Which is the best technique to assess status of vitamin A liver stores?
- Aserum retinol levels
- Bthe relative dose response
- Cclinical eye examinations
89Imagine you are a nutritionist working in a country other than the U.S. Which is an assumption about vitamin D status that is NOT true?
- AThe latitude makes a difference as regards how much vitamin D can be self-synthesized
- Bcustoms of dress make a difference as regards to how much vitamin d can be self-synthesized
- CCows milk is a reliable source of vit D in the food supply
- Dskin color can make a difference as regards to how much sun is needed to synthesize vit D
90Which vitamin D molecule would you expect to see in fortified foods?
- Aergocalciferol
- Bcalcidiol
- Ccalcitriol
- Dcholecalciferol
91What % of vitamin D from the diet is absorbed?
- A20
- B30
- C40
- D50
92Dietary cholecalciferol must be further hydroxylated in order to be active vitamin D. The first hydroxylation occurs in the _____ to produce _____.
- Aliver, 25-hydroxycholecalciferol
- Bkidney, 25-hydroxycholecalciferol
- Cskin, 7-dehydrocholesterol
- Dkidney, 1-hydrocholesterol
93What form of vitamin D is the major circulating form with a half-life of approximately 3 weeks?
- Acalcidiol
- Bcalcitriol
- Ccholecalciferol
- Dvit D2
94Which vitamin is believed to function like a steroid hormone?
- Acholine
- Bvit A
- Cvit D
- Dvit E
95Choose the non-genomic effect of vitamin D.
- Aincreased synthesis of calbindin
- Bbone accretion
- Crapid calcium absorption
- Dintracellular cytosolic signal transduction
96The vitamin D response element (VDRE) is found
- Aon the enterocyte membrane
- Bon the renal tubule
- Cin the nucleus
- Din the pancreatic duct cell
97Which vitamin has as its primary function the maintenance of calcium homeostasis?
- AA
- BD
- CE
- DK
98Choose the correct order of the phrases below to explain the response of the body to a decline in serum calcium levels. Choose the BEST answer.
1. Increased release of PTH
2. Decreased release of PTH
3. Increased synthesis of calbindin
4. Increased synthesis of 1,25-(OH)2 D3
5. Increased bone absorption
6. Increased calcium absorption
7. Decreased bone resorption
8. Increased calcium excretion
9. Increased bone resorption- A1, 5, 4, 8
- B1, 3, 5, 9
- C2, 3, 9, 6
- D1, 4, 3, 6
99What vitamin is associated with diminished proliferation and enhanced differentiation of cells, which serves as a basis for its use as treatment of skin diseases such as psoriasis?
- AA
- BE
- CK
- DD
100If asked about the relationship of vitamin D to autoimmune disease, the best information for a dietetic professional to provide is:
- AEvidence does not support a relationship
- Bevidence is only in animals, not humans
- Csome evidence suggests a protective effect of vit D
- Dtake a supplement containing 2000 IU vit D each day
101A deficiency of which vitamin is commonly associated with rickets?
- AA
- BD
- CE
- DK
102Toxicity of which vitamin is related to increased deposition of calcium in soft tissues?
- Alipoic acid
- Bbiotin
- CD
- DE
103What is a symptom of a vitamin D toxicity?
- Ahypercalemia
- Bhypocalemia
- Crickets
- Dosteoporosis
104Sun exposure does not cause hypervitaminosis D because _____.
- Acutaenous production of vitamin reaches a max
- Bsunburned skin is not sensitive to the UV wavelength that causes previt D3 synthesis
- Cinactive products are synthesized from previt D3 and D3
- Dvitamin D-binding protein is not saturated with vit D3
105In assessing the vitamin D status of an individual, which measure would you use?
- Acirculating 25-OH cholecalciferol
- Bcirculating 1, 25-OH cholecalciferol
- Ccirculating cholecalciferol
- Dserum calcium
106Which tocopherol form provides the most vitamin E activity in the U.S. food supply?
- Aalpha
- Bbeta
- Cgamma
- Ddelta
107How does alpha-tocopherol differ from beta-tocopherol?
- Asaturation of side chain
- Blocation of methyl groups
- Csource in diet
108A genetic deficiency in _____ leads to a vitamin E deficiency syndrome.
- ARRR alpha tocopherol
- Bgamme tocotrienol
- Ctocopherol carrier protein in the jejunum
- Dalpha tocopherol transfer protein in the liver
109Immediately following a balanced meal that contained vitamin E (such as fortified milk), where would you most likely find most of the vitamin E in the body?
- Aportal blood as alpha tocopherol
- Bin the general circulation bound to RBC
- Cinside cells as free alpha tocopherol
- Dadipose tissue
- Ein chylomicrons in the lymphatic vessels and general circulation
110In what type of tissue is the largest amount of vitamin E stored?
- Aadipose
- Bheart
- Clung
- Dbrain
111What vitamin is stored in the adipose tissue?
- AD
- BE
- CA
- DK
112Which vitamin is associated with improved plasma membrane structure and glucose transport/metabolic control in people with type 2 diabetes?
- AA
- BD
- CE
- DK
113Which of the fat-soluble vitamins is consumed in the form of phylloquinone from plant foods?
- AA
- BD
- CE
- DK
114Which fat-soluble vitamin appears to operate as a coenzyme that modifies proteins to bind with calcium?
- AA
- Bbeta carotene
- CE
- DK
115The action of vitamin K is the post-translational synthesis of blood clotting factors occurs:
- Ain the blood
- Bin the liver
- Cin the small intestine
- Din the bone marrow
116Anticoagulant drugs that act by inhibiting vitamin K activity do so by which mechanism?
- Ainhibiting formation of the active form of vit K
- Binterfering with micelle formation so vit K is not absorbed
- Cnot allowing calcium to interact with Gla residues
- Dstimulating osteocalcin synthesis
117Mr. S. takes warfarin due to his valve replacement surgery. He is an avid gardener and enjoys eating the many green leafy vegetables he grows. You caution Mr. S. to tell his physician about this because the amount of warfarin he takes may need to be _____
- Adecreased
- Bincreased
118Risk of vitamin K deficiency is greatest in
- Anewborns
- Bchildren
- Cteens
- Delderly
119Vitamin K deficiency in adults is most likely due to
- Aoxalic acid in food
- Bachlorhydria
- Cantibiotic therapy
- Da high-fiber diet
120For which vitamin is a severe deficiency associated with an increased tendency for bleeding?
- AA
- BD
- CE
- DK
121Which is the best measure of vitamin K status?
- Ades-y-carboxyglutamic prothrombin
- Bprothrombin time
- CINR
- DPTH concentration
122Gut bacteria can produce some vitamins, but this rarely contributes to our requirements because they are not absorbed.
- AVerdadero
- BFalso
123Because β-carotene can be converted into retinol, plant sources are referred to as preformed vitamin A.
- AVerdadero
- BFalso
124Production of active vitamin D requires skin, sunlight, cholesterol, the liver, and the kidneys.
- AVerdadero
- BFalso
125Calcium homeostasis in the blood depends on intestinal absorption, bone resorption, and kidney reabsorption.
- AVerdadero
- BFalso
126Many anticoagulants inhibit the vitamin K cycle, thereby preventing activation of clotting proteins.
- AVerdadero
- BFalso
127All three forms of vitamin A (retinol, retinal, retinoic acid) are stored in the liver as retinyl esters.
- AVerdadero
- BFalso
128Vitamin D increases the abundance of calbindin (Ca++ transporter) in enterocytes by increasing the transcription of the calbindin gene.
- AVerdadero
- BFalso
129Rhodopsin is simply the opsin protein after it has been activated by 11-cis-retinal.
- AVerdadero
- BFalso
130Many anticoagulants work by inhibiting the regeneration of active vitamin K (i.e., dihydrovitamin KH2) during the vitamin K cycle.
- AVerdadero
- BFalso
131All of the functions of vitamin A are carried out by retinoic acid via transcriptional mechanisms.
- AVerdadero
- BFalso
132A good source of vitamin D is milk, because it is fortified with 1,25-(OH)2-vitamin D3.
- AVerdadero
- BFalso
1337-dehydrocholesterol is the form of vitamin D that is added to fortify milk.
- AVerdadero
- BFalso
Información
- Descripción
- Test sobre Exam 5 - Vitamins CH 9 & 10, creado por Ella Buxton el 20/04/2017.
- Autor
- Ella Buxton
- Idioma
- English
- Visitas
- 12
- Valoración
- Aún sin valoraciones Valora este test