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niacin fortified avitaminosis vitamin С diarrhoea water-soluble deficiency visual supply antioxidant |
1. In much of the developed world, vitamin deficiencies are rare; this is due to (1) an adequate... of food and (2) the addition of vitamins and minerals to common foods, often called fortification.
2. The В vitamins are a group of... vitamins that play important roles in cell metabolism.
3. Human bodily stores for different vitamins vary widely; vitamins A, D, and B12 are stored in significant amounts in the human body, mainly in the liver, and an adult human's diet may be deficient in vitamins A and D for many months and B12 in some cases for years, before developing a... condition.
4. However, vitamin B3 (... and niacinamide) is not stored in the human body in significant amounts, so stores may last only a couple of weeks.
5. An increase in the proportion of animal protein in the 20th century American diet coupled with increased consumption of milk... with relatively small quantities of vitamin D.
6. In living organisms, ascorbate is an since it protects the body against oxidative stress.
7. Scurvy is an... resulting from lack of vitamin C, since without this vitamin, the synthesized collagen is too unstable to perform its function.
8. A 1992 study found that taking 2 grams... daily lowered blood histamine levels 38 percent in healthy adults in just one week.
9. When taken in large doses, ascorbic acid causes... and other forms of indigestion in healthy subjects.
10. The role of vitamin A in the... cycle is specifically related to the retinal form.
5. Complete the sentences by choosing the appropriate prepositions. Translate the completed text into Ukrainian.
Vitamins are classified by/with their biological and chemical act ty, not their structure. Thus, each "vitamin" refers to/on a number in/of vitamer compounds that all show the biological activity associated by/with a particular vitamin. Such a set of/in chemicals is grouped under/above an alphabetized vitamin "generic descriptor" title, suck as "vitamin A", which includes the compounds retinal, retinol, four known carotenoids. Vitamers by/with definition are convertit for/to the active form of/for the vitamin in/at the body, and are sometimes inter-convertible to/for one another, as well.
Until/After the mid-1930s, when the first commercial yeast-extr and semi-synthetic vitamin С supplement tablets were sold, vitar were obtained solely through food intake. Therefore changes at/in j (which, for example, could occur during/before a particular grov season) could alter the types and amounts of/in vitamins ingested. Vitamins have been produced as commodity chemicals and made widely available as inexpensive semisynthetic and synthetic-source multivitamin dietary supplements, since/after the middle of the 20" century.
The term vitamin was derived from/out 'vitamine', a combinati word made up by/with Polish scientist Casimir Funk out/from vi and amine, meaning amine of/for life. It had been suggested in 1912 that the organic micronutrient food factors that prevent berit and perhaps other similar dietary-deficiency diseases might be cher cal amines. This proved incorrect for/to the micronutrient class. on 1920, Jack Cecil Drummond proposed that the final 'e' be dropp to deemphasize the "amine" reference, after researchers began suspect that not all 'vitamines' (in/at particular, vitamin A) have amine component. So the word 'vitamine' was shortened to/by vitamin.
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