FNU 404 Exam 3 Questions And
Correct Answers
folic acid - Answer oxidized form found in fortified foods and supplements
folate - Answer reduced form found naturally in foods and tissues
folate is found in - Answer vegetables
folate has a higher - Answer concentration in raw foods than cooked
folate is destroyed by - Answer heat, oxidation, and UV light
folate supplements can - Answer mask B12 deficiency
more americans are meeting their folate recommendations because of - Answer
enriched and fortified foods
folate is synergistic with - Answer vitamin B12
folate is excreted in the - Answer urine and feces
folate deficiency - Answer megaloblastic macrocytic anemia
what does the assessment of nutriture of folate include? - Answer plasma, serum, or
RBC concentration, FIGLU excretion, deoxyuridine suppression test, functional marker
of folate and vitamin B12 deficiencies: elevated plasma homocysteine concentrations
Dietary folate equivalent= - Answer ug food folate = (1.7 x ug folic acid)
folate digestion, absorption, transport, and storage - Answer Polyglutamate forms
hydrolyzed to monoglutamate form, (Folate in fortified foods already in monoglutamate
form), Reduced to THF in enterocytes, Transported in portal circulation as 5-methyl THF
by proton-coupled folate transporter (PCFT), Found as a monoglutamate in blood
folate functions and mechanisms of action - Answer amino acid and choline metabolism
(serine and glycine degradation, choline degradation, histidine degradation, methionine
and SAM (s- adenosyl methionine) synthesis), gene expression, purine and pyrimidine
synthesis/ nucleotide metabolism, associations with disease
vitamin B12 is released from - Answer food in the acid environment of the stomach and
with the help of pepsin
vitamin B12 binds to - Answer R proteins found in saliva and gastric juice. the B12 R
protein complex travels from the stomach to the duodenum
within the alkaline environment of the duodenum, R protein - Answer is digested to
,release vitamin B12
in the duodenum, vitamin B12 - Answer binds and forms a complex with intrinsic factor
(IF) which was made by gastric parietal cells
within the ileum, vitamin B12 IF complex - Answer binds to specific receptor and is
internalized by endocytosis
what does vitamin B12 do in the stomach? - Answer it is released from proteins/
polypeptides. binds to an R protein
what does vitamin B12 do in the duodenum? - Answer R protein is hydrolyzed- free
cobalamin. binds to intrinsic factor
what does vitamin B12 do in the ileum? - Answer it is absorbed via binding with
receptors (cubilins). binds to transcobalamin II for transport.
what does vitamin B12 do in the blood? - Answer it is bound to one of three cobalamins.
TCII- main protein that carries newly absorbed cobalamin in 1:1 ratio, TCI and TCIII-
exact functions unknown. lack of stomach acid can impair absorption, can be stored
and retained in the body for long periods.
functions and mechanisms of action of vitamin B12 - Answer conversion of
homocysteine to methinonine and conversion of L- methulmalonyl CoA to succinyl CoA
metabolism and excretion of vitamin B12 - Answer undergoes little to no degradation
prior to excretion, 0.1%/ day excreted in bile, most reabsorbed in the ileum
vitamin B12 is sourced primarily from - Answer animal products. people with vegan diets
are more at risk for deficiencies. vegans should take synthetic products.
sources of vitamin B12 - Answer meat and meat products, dairy contains less, but
absorption may be better, plant- derived foods sometimes fortified (breakfast cereals)
vitamin B12 deficiency - Answer megaloblastic macrocytic anemia, may cause
neurologic problems
inadequate intake of vitamin B12 is most likely to occur with - Answer vegan diets
toxicity of vitamin B12 - Answer none observed, no tolerable upper intake level
vitamin B12 assessment of nutriture - Answer serum concentrations, can be maintained
at expense of tissues
vitamin B 12 deficiency causes - Answer altered gastric pH, parietal cell destruction
causing insufficient intrinsic factor (may result from atrophic gastritis, pernicious
anemia, or other conditions), impaired pancreatic exocrine, gastric, or intestinal
functions, use of nitrous oxide
what 3 tests can be done to assess vitamin B deficiency? - Answer methylmalonic acid
, test, deoxyuridine suppression test, schilling test
vitamin - Answer substance that is organic and is an essential player in at least one
necessary chemical reaction or process in the body
conditionally essential vitamins - Answer not normally essential, but can become
essential in certain disease states
non- essential vitamins - Answer can produce on our own
features of vitamins - Answer cannot be made in the body, don't have calories
(noncaloric). don't provide energy, required in small amounts (mg and mcg)
what are the four fat soluble vitamins? - Answer A, D, E, K
digestion and absorption of fat- soluble vitamins are greatest when - Answer some
dietary fat is present
absorption of fat- soluble vitamins is greatest from the - Answer jejunum
fat- soluble vitamins are stored in body tissues in greater quantities than in - Answer
water- soluble vitamins
it is less likely to get a - Answer fat- soluble vitamin deficiency than water soluble
vitamins
vitamin a functions - Answer synthesis of rhodopsin, cell growth, cell differentiation,
bone development, and immune function antioxidant
food sources of vitamin A - Answer liver, dairy products, and fortified foods, sweet
potato, carrots, spinach, butternut squash, greens, broccoli, and cantaloupe
vitamin D functions - Answer regulator of bone mineral metabolism, blood calcium
homeostasis, cell differentiation, proliferation, and growth
food sources of vitamin D - Answer fatty fish and their oils, and fortified foods
what are all the forms of vitamin A? - Answer retinol, retinal, and retinoic acid,
provitamin, carotenoids
what are all the forms of vitamin D? - Answer D2 (ergocalciferol), D3 (cholecalciferol),
provitamin-7- dehydrocholesterol
what are the forms of vitamin E? - Answer tocopherols and tocotrienols
what are the forms of vitamin K? - Answer phylloquinones and menaquinones
function of vitamin E - Answer antioxidant
food sources of vitamin E - Answer vegetable oils, nuts, and seeds