Water Soluble Vitamins Problem Set

Transcription

1 MEDCHEM 562 Winter 2013 Water Soluble Vitamins Problem Set 1) Which water-soluble vitamin(s) is/are appreciably stored in the body? b. Vitamin B2 d. one. All water-soluble vitamins are readily eliminated renally. 2) Isoniazid is an antituberculosis drug that forms a Schiff base with which vitamin? b. Vitamin B5 d. Vitamin B7 3) Enriched products typically have which vitamins? (You may circle more than one answer for this question) b. Vitamin B2 c. Vitamin B3 4) Studies show thiamin deficiency in 20-30% of elderly patients and 40-50% of chronic alcoholics. a. ame three early signs of deficiency: b. ame three late signs of deficiency: 5) Question 5 H 2 S a. Which vitamin is shown above?

2 b. Circle the ring that is important for the chemistry that occurs with this vitamin. c. The vitamin shown above is used to harvest energy from carbohydrate metabolism. ame two types of reactions discussed in class that the vitamin participates in: i. ii. 6) Vitamin B6 is involved in tryptophan metabolism to make serotonin and which vitamin? 7) Question 7 H H a. Circle the hydroxyl group that gets phosphorylated to make FM. b. ame the vitamin shown above: c. Is the vitamin shown in the oxidized or reduced form? d. Draw the other form (oxidized or reduced) of the vitamin in the space provided to the right of the arrows. Label which form is reduced and which is oxidized. Indicate which direction involves a gain or loss of protons (above or below the arrow): H?? H

3 8) The glutathione pathway was discussed in the fat-soluble vitamin lectures and is shown below (diagram taken from course notes). Since then, two water-soluble vitamins have been discussed which have important roles in the pathway below. a. The glutathione pathway depends on an adequate supply of which two water-soluble vitamins? i. ii. 9) Vitamin B6 is involved in which of the following reactions? a. Transamination b. Ribosylation of proteins in cell signaling and DA replication and repair c. Regeneration of Vitamin E d. xidative decarboxylation of α-ketols 10) Which vitamin would you suggest a woman contemplating pregnancy to take a supplement for (as it prevents neural tube defects in the unborn)? 11) Which vitamin supplement would you recommend to a vegan patient (since a major source of the vitamin comes from meats)? a. Vitamin B3 b. Vitamin B6 c. Vitamin B9 d. Vitamin B12

4 12) Vitamin B6 is involved in tryptophan metabolism to make serotonin and which vitamin? 13) The structure of 4-deoxypyridoxine is shown below. It is an antagonist of which vitamin? 14) Deficiency in Vitamin B12 results in deficiency in which other vitamin? 15) Deficiency in the vitamin from question 14 is linked to Vitamin B12 because: a. FM is only converted to FAD in the absence of B12 b. TMP cannot be converted to TPP in the absence of B12 c. Conversion of dopamine to norepinephrine does not occur in the absence of B12 d. 5-MeTHFA is not converted back to THFA in the absence of B12 16) Which Vitamin C dose range is best to prescribe to patients (hint: think about bioavailability vs dosage)? a. 200 mg 500 mg/day b. 500 mg 1000 mg/day c mg 1250 mg/day d. >1250 mg/day 17) How is Vitamin B12 deficiency diagnosed? a. Measure methyl malonic acid in plasma b. Measure erythrocyte transaminases c. Measure pyruvate levels in the plasma d. Measure ADPH levels

5 18) Avidin is a protein found in egg whites that can lead to a deficiency state in which vitamin? b. Vitamin B5 c. Vitamin B7 d. Vitamin B12 19) What would you prescribe to a patient for improving serum lipids? a. iacin b. iacinamide c. Biotin d. Pantothenic acid 20) Scurvy is a deficiency state of which vitamin? c. Vitamin B9