Пользуясь моделью, переведите данные словосочетания на русский язык.
| fat-like substance жироподобное/жирообразное вещество |
powder-like material; protein-like constituent; dough-like mass; gelatin-like medium; circle-like structure; stone-like bread
The food constituents known as vitamins are exceedingly important in nutrition even though they are required only in small amounts. Vitamins are essential for good nutrition and health and for normal growth and development. Those vitamins that are generally recognized as essential, and some of those that may be essential, are considered here. Though many vitamins are available in the form of concentrated or in pure synthetic preparations, or both, foods still remain the best source of these important substances.
Vitamin A was first discovered in butter, egg yolk, fish liver oil, and green vegetables. It stimulates growth and aids in general well-being. Vitamin A occurs as such in animal foods. It occurs in certain vegetables as carotene or provitamin A, a bright yellow pigment which the body changes to vitamin A. This vitamin is stable to heat and, since it is a fat-soluble substance, does not dissolve to any appreciable extent in water. But it is not stable to light, especially ultra-violet light. Foods which are rich in vitamin A are butter, cheese, cream, eggs, fish oil, fruits, liver, milk.
Vitamin D. The antirachitic or “sunshine” vitamin, is really “stored sunshine” in food. This storage is due to the presence of ergosterol, a fat-like substance in food, which is called a provitamin D, and under direct exposure to the sun or to ultraviolet light for short daily periods, this substance is converted into vitamin D within the body. Unlike most of the other vitamins, this one is not easily destroyed and is stable to heat, alkalis1, acids, and oxidation. Vitamin Dis essential for the development and maintenance of bones and teeth. Yeast contains ergosterol which can be irradiated by ultraviolet light and thus transformed into vitamin D. Sources of vitamin D are: butter and egg yolk, fish liver oil, oily fish.
Vitamin E affects reproduction and fertility growth, muscle tone and the condition of the nervous system. It has also a function in preventing the destruction of other foods through oxidation. The best sources of vitamin E are the vegetable oils, butter, eggs, green leaves and liver.
Vitamin K is necessary for normal clotting2 of the blood. Heat has little effect upon vitamin Kand, like the ether fat-soluble vitamins, it is not soluble in water. Alkalis1, strong acids and sunlight destroy this vitamin. Foods rich in vitamin K are cabbage, cauliflower, fish liver.
Ascorbic acid, known as vitamin C is the least stable of all the vitamins. It oxidizes readily, and in the presence of heat, alkali1, and oxygen, oxidation goes on rapidly. Ascorbic acid is water-soluble. The best sources of this vitamin include: citrus fruits, peppers, strawberries, vegetables, tomatoes.
1 –alkali – щелочь мн.ч. – s/-es
2 - свертывание
Задания
1. Ответьте на вопросы:
1. Why are vitamins essential in our nutrition? 2. In what form may vitamins be available? 3. What is the best source of vitamins?
2. Заполните пропуски и переведите словосочетания на русский язык.
a) exposing; b) exposure; c) to be exposed
1. … vitamins to the sun or ultra-violet light 2. under direct … to air 3. the substance … to sun light
a/destroying b/destroyed c/destruction
1. foods … through oxidation 2. the way of … vitamins 3. the … of vitamins due to long heating
a/having recognized b/recognition c/recognized
1. the … of the significance of vitamins 2. the process generally … as an extremely complex one 3. … the existence of vitamins scientists began to study their properties
a/to be converted b/conversion c/converting
1. a provitamin … into a vitamin 2. … provitamin D into vitamin D under direct exposure to ultra-violet light 3. the necessity of the … of provitamin D into vitamin D within the body
a/affected b/to be affected c/having been affected
1. … by heat the substance changed its properties 2. vitamin A … by light, especially by ultra-violet light 3. the substance … by light in order to destroy it
2. Укажите номера синонимичных пар.
1. convert 2. exceedingly 3. occur 4. expose 5. aid 6. reproduce 7. essential 8. affect 9. constituent 10. easily
1. help 2. readily 3. transform 4. influence 5. happen 6. lay open to 7. vital 8. generate / multiply 9. component 10. extremely
3.Укажите номера антонимичных пар.
1. stimulate 2. presence 3. include 4. strong 5. destroy 6. rapidly 7. rich in 8.stable 9. soluble 10. appreciable
1. deficient in 2. exclude 3. create 4. insoluble 5. inconsiderable 6. changeable 7. weak 8. prevent 9. slowly 10. absence
4.Назовите пропущенные предлоги.
1. most of vitamins are stable ... heat. 2. under the direct exposure ... light. 3. to be converted ... vitamin A. 4. to be rich ... vitamins 5. to oxidize readily ... the presence of acids. 6. to be able to transform carotene ... vitamin A. 7. necessary ... normal clotting of blood. 8. provitamin D is converted ... vitamin within the body. 9. essential... the development and maintenance of bones and teeth. 10.a fat-soluble vitamin is not soluble ... water
1. into 2. in 3. to 4. for
«FROM THE HISTORY OF VITAMINS»
1. Прочитайте текст и скажите, какое открытие было сделано польским ученым.