Vitamin

1. Vitamin is any of several organic substances that usually are separated into water-soluble (e.g. the B vitamin, vitamin C) and fat-soluble (e.g. vitamin A, D, E, K) groups; small quantities are necessary for normal health and growth in higher forms of animal life.

2. The substances commonly known as vitamins are diverse in chemical structure and function. Originally defined as organic compounds obtainable in a normal diet and capable of maintaining life and promoting growth, vitamins are distinct from carbohydrates, fats, and proteins in function. As well as in the quantities in which organisms require them. A number of compounds once grouped with vitamins no longer are considered vitamins. If a vitamin is absent from diet or is not properly absorbed by an organism, a specific deficiency disease may develop.

3. The term “vitamin” originated from “vitamine” a word first used in 1911 to designate a group of compounds vital for life. Since they generally cannot be synthesized by an animal (or, if synthesized, the amounts are insufficient to meet body needs) and must be obtained from the diet or from some synthetic source, vitamins are called essential nutrients. The requirements for some of the B vitamins may be met in part by bacterial synthesis in the intestines of some mammals. The amino acid tryptophan can be converted to nicotinic acid and thus can serve as a source for part of the nicotinic acid required by an animal.

4. Vitamin C can be synthesized by some organisms in sufficient amounts so that the dietary requirement is eliminated: vitamin C usually is considered a vitamin, however, because it must be included in the diet of man. Vitamins are distinct from many other compounds, which although indispensable for proper animal functions, can be synthesized in adequate quantities.

ЗАДАНИЕ №27 (выберите один вариант ответа)

Определите, является ли утверждение:

The chemical structure of vitamins is diverse.

ВАРИАНТЫ ОТВЕТОВ:

A истинным B ложным C нет информации

ЗАДАНИЕ №28 (выберите один вариант ответа)

Определите, является ли утверждение:

Vitamin C belongs to a water-soluble group of vitamins.

ВАРИАНТЫ ОТВЕТОВ:

A истинным B ложным C нет информации

ЗАДАНИЕ №29 (выберите один вариант ответа)

Определите, является ли утверждение:

Vitamin C cannot be synthesized in adequate quantities by any organisms.

ВАРИАНТЫ ОТВЕТОВ:

A истинным B ложным C нет информации

ЗАДАНИЕ №30 (выберите один вариант ответа)

Определите, является ли утверждение:

The quantity of vitamin C required by an organism amounts to 500 mg a day.

ВАРИАНТЫ ОТВЕТОВ:

A истинным B ложным C нет информации

ЗАДАНИЕ №31 (выберите один вариант ответа)

Укажите, какой части текста (1, 2, 3, 4) соответствует следующая информация:

The amounts of vitamins synthesized by any animal are insufficient to meet body needs.

ВАРИАНТЫ ОТВЕТОВ:

A 1 B 2

C 3 D 4

ЗАДАНИЕ №32 (выберите один вариант ответа)

Укажите, какой части текста (1, 2, 3, 4) соответствует следующая информация:

There are various vitamins in terms of their function.

ВАРИАНТЫ ОТВЕТОВ:

A 1 B 2

C 3 D 4

ЗАДАНИЕ №33 (выберите один вариант ответа)

Ответьте на вопрос:

Where do vitamins come to an organism from?

ВАРИАНТЫ ОТВЕТОВ:

A They are converted from a sufficient vitamin.

B They are synthesized by an animal.

C They are obtained from the diet or from some synthetic source.

D They are converted from fats.

ЗАДАНИЕ №34 (выберите один вариант ответа)

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