3. Fat Soluble Vitamins vs. Water Soluble Vitamins

5.  Found in fats and oils  Require bile for absorption  Enter the lymph, then the blood  Held and stored in fatty tissues  Needed in small amounts  May reach toxic levels  Not readily excreted

7.  Vision  Maintain epithelial tissue and skin  Support reproduction and growth  Immune system  Bone development

8. Deficiency – Infectious disease Pneumonia, measles, diarrhea – Keratinization Dry, rough, scaly skin – Night blindness

9. body can make vit D −from sunlight −precursor made from cholesterol production occurs in liver and kidney diseases can affect activationsources  fortified food: milk, margarine, cereals, beef, eggs  sun  storage from the summer does not last the winter

11.  part of the bone-making/maintenance team  maintains blood concentrations of Ca & P  Mineralization of bones −raises blood calcium and phosphorus by increasing absorption from digestive tract −withdrawing calcium from bones −stimulating retention by kidneys  deficiencies  ultimately creates a calcium deficiency  osteomalacia or rickets

12. antioxidant – defender against free radicals polyunsaturated fatty acids may reduce the risk of heart disease widespread in food – easily destroyed by heat processing deficiencies – rare – erythrocyte hemolysis An antioxidant is a molecule that inhibits the oxidation of other molecules.

13. Aids in blood clotting and Bone mineralization Deficiency causes hemorrhagic disease Sources – Made by bacteria in GI tract – Absorbed and stored in liver

16. Co-enzymes (activate enzymes) Found in the same foods – Single deficiency rare Act together in metabolism – Metabolic pathways used by protein, carbohydrate, and fat

17.  Thiamin (B1)  Riboflavin (B2)  Niacin (B3)  Pantothenic Acid  Biotin  Pyridoxine (B6)  Folate  Vitamin B-12

19. Synthesized by most animals (not by humans) Decrease absorption with high intakes Excess excreted

20. Citrus fruit Potato Green pepper Cauliflower Broccoli Strawberry Romaine lettuce Spinach

21. Reducing agent (antioxidant) Iron absorption (enhances) Synthesis of collagen Immune functions Does not prevent colds, but may reduce duration of symptoms by a day Wound healing Easily lost through cooking Sensitive to heat Sensitive to iron, copper, oxygen

22. Vitamin C (ascorbic acid) deficiency leads to scurvy, a disease characterized by weakness, small hemorrhages throughout the body that cause gums and skin to bleed, and loosening of the teeth. Sailors that were out at sea for months on end would often develop scurvy unless the captain had the foresight to pack limes and other citrus fruits. In the U.S., deficiency is seen mostly in alcoholic persons with poor diets and older persons who eat poorly (no fresh fruits and vegetables)

23. Scorbutic Rosary Follicular Hemorrhages

24. Hemochromatosis – Vitamin C enhances iron absorption Oxalate kidney stones Erodes tooth enamel

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28. Potassium iodide must be added in excess to keep iodine dissolved. Once all the ascorbic acid has been consumed, any excess iodine will remain in solution. Since aqueous iodine solutions are brown in colour, iodine can act as its own indicator. However, it is quite difficult to detect endpoints using iodine coloration alone, and it is more usual to add starch, which forms an intensely blue coloured complex with iodine but not with the iodide ion.

29. The addition of acid is necessary to provide the acidic conditions required in reaction (1) above. The endpoint of the titration is the first permanent trace of a dark blue-black colour due to the starch-iodine complex.

31. Molecular iodine (I2) is only slightly soluble in water but adding iodide, I-, produces the "triiodide" ion (I3-) in solution. Thus, KI is almost always added when redox reactions of I2 are involved in quantitative analysis. I2(s) + I-(aq) I3(aq) Iodine iodide triiodide Starch is used as the indicator in most iodometric titrations because iodine (i.e., I3)forms an intense blue colored "starch-iodine complex."

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33. According to the above reactions, each mole of potassium iodate added corresponds to 3 moles of ascorbic acid dehydrogenated in the sample.

34. 1. Pipette 25 ml of the provided ascorbic acid solution into a 250 ml conical flask, 2. Add  4 ml of 2 M HCl, 3. Add  5 ml of potassium iodide (KI) solution and 3 ml starch solution. 4. Then titrate with the standard potassium iodate (KIO 3 ) solution until the solution turns intense blue. Write down the standard potassium iodate (KIO 3 ) solution volume. 5. Pipette 25 ml of an unknown ascorbic acid sample, a kind of juice, into a 250 ml conical flask, then follow the same procedure of steps 1-4 and write down the volume of the standard KIO 3 solution determine the concentration (mol/ml) of ascorbic acid in the selected sample. 34

35. procedure