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| 9097298801 | structure of folic acid | pteroylglutamic acid consists of the base pteridine attached to one molecule each of p-aminobenzoic acid (PABA) and glutamic acid | 0 | |
| 9097328400 | forms of folic acid | in plants folic acid is present as polyglutamate conjugate the active form of folic acid is tetrahydrofolate (THF) | 1 | |
| 9097353136 | sources of folic acid | -green leafy vegetables fruits wheat germ liver kidney yeast | 2 | |
| 9097374313 | what it is the required level of folic acid for adults and pregnant females | adult man/nonpreg woman: 100ug/day pregnant woman: 300ug/day | 3 | |
| 9097379580 | functions of folic acid | important in DNA synthesis helps development of neural tube in fetus acts as a coenzyme | 4 | |
| 9100103452 | how does folate and B12 interact in the folate trap | it is the only closely linked metabolism of two vitamins: folic acid and vitB12 known in humans Sometimes, despite sufficient availability of folates, an intracellular deficiency of biologically active THF arises. The conversion os 5-methyl-THF is necessary to maintain the folate cycle and dependent on vit B12 to remethylate homocysteine to methionine (regenerating THF) The methyl group transfer is therefore greatly dependent on 5-methyl-THF and the availability of Vit B12. | 5 | |
| 9100112321 | what are the functions of Vit B? | it is needed as a coenzyme for two biochemical reactions: first, as methyl B12, it is a cofactor for methionine synthase, the enzyme responsible for methylation of homocysteine to methionine using methyl tetrahydrofolate and methyl donor. second as deoxyadenosyl B12, it assists in conversion of methyl malonyl coenzyme A (CoA) to succinyl CoA | 6 | |
| 9100147992 | Absorption of folic acid | dietary folates (a complex mixture of variously reduced and polyglutamated folates) are all converted to one compound, methyltetrahydrofolate (methyl THF), a reduced monoglutamate (PteGlu1) form which circulates in plasma. the intestinal absorption of PteGlu7 requires deconjugation by a brush-border peptidase to PteGlu1 folate movement across the apical membrane is linked to the efflux of OH- the mechanism of folate moevement out of the epithelial cell across the basolateral membrane is not understood and only occurs in the proximal small intesting at a pH of 5 | 7 | |
| 9100244833 | causes of folate deficiency | inadequate intake increased requirements malabsorption due to sprue drugs (like methotrexate) | 8 | |
| 9100246830 | what does folate deficiency manifest as clinically? | megaloblastic anemia hyperhomocysteinemia | 9 | |
| 9100247684 | tests for folate deficiency | rise in urinary excretion of Formimino glutamate (FIGLU) after a large dose of histidine. This is because histidine will be converted to FIGLU which is converted to glutamate by THF and then excreted. | 10 | |
| 9100255029 | structure of vit B | it is a corrin ring (similar to a porphyin ring) with a cobalt ion at its center | 11 | |
| 9100257925 | what are the forms of vit B | cyanocobalamin hydroxocobalamin metylocobalamin deoxyadenosylcobalamin | 12 | |
| 9100261979 | sources of VitB | milk and milk products liver kidney other fleshy foods | 13 | |
| 9100263228 | functions of Vit B | dna synthesis and cell division neural tube function THF recovery and SAM -- adenosylmethionine | 14 | |
| 9100320015 | Phases of vit B absorption | 1. Intragastric Events -release of B12 from food proteins by the acid pH and pepsin in stomach -binding of B12 by R-protein or haptocorrin which is secreted by gastric glands 2. Duodenal and jejunal events -degradation of R-protein by pancreatic proteases and HCO3- (alkaline secretions) -binding of B12 by intrinsic factor (IF) which is secreted by gastric parietal cells. 3. Ileal events -attachment of B12-IF to receptor, ileal enterocyte absorbs B12-IF complex -transport of B12 across enterocyte -binding of B12 by transcobalamin II in portal blood. | 15 | |
| 9100338686 | causes of vitamin B12 deficiency | reduction in intestinal absorption due to -inadequate intrinsic factor - disorders (Sprue,enteritis) - fish tapeworm and bacteria | 16 | |
| 9100340754 | what does deficiency in VitB manifest as | pernicious anemia peripheral neuropathy homocysteinuria. | 17 | |
| 9100342246 | tests for Vitamin B deficiency | schilling test- tests how well the body absorbs Vit B from the gastrointestinal tract. the urinary excretion of methylmalonyl CoA | 18 | |
| 9100370255 | describe the process of the schilling test | the test is performed by administering a radioactive oral dose of cyanocobalamin to a patient that has fasted. They are injected with vitB intramuscularly. Urine collected. Less than 7% excretion represents abnormal findings and indicates that poor absorption of the oral test dose occured. if abnormal, stage II preformed on patient. Intrinsic factor is administered alongside oral dose of VitB. If poor absorption of Vit B persists, the patient has pernicious anemia. |  | 19 |
