приложение 1

Text Vitamins

A vitamin is an organic compound required as a nutrient in tiny amounts by an organism. A compound is called a vitamin when it cannot be synthesized in sufficient quantities by an organism, and must be obtained from the diet. Thus, the term is conditional both on the circumstances and the particular organism. For example, ascorbic acid functions as vitamin C for some animals but not others, and vitamins D and K are required in the human diet only in certain circumstances.

Vitamins are classified by their biological and chemical activity, not their structure. Thus, each "vitamin" may refer to several vitamer compounds that all show the biological activity associated with a particular vitamin. Such a set of chemicals are grouped under an alphabetized vitamin "generic descriptor" title, such as "vitamin A," which includes the compounds retinal, retinol, and many carotenoids. Vitamers are often inter-converted in the body. The term vitamin does not include other essential nutrients such as dietary minerals, essential fatty acids, or essential amino acids, nor does it encompass the large number of other nutrients that promote health but are otherwise required less often.

Vitamins have diverse biochemical functions, including function as hormones (e.g. vitamin D), antioxidants (e.g. vitamin E), and mediators of cell signaling and regulators of cell and tissue growth and differentiation (e.g. vitamin A). The largest number of vitamins (e.g. B complex vitamins) function as precursors for enzyme cofactor biomolecules (coenzymes), that help act as catalysts and substrates in metabolism. When acting as part of a catalyst, vitamins are bound to enzymes and are called prosthetic groups. For example, biotin is part of enzymes involved in making fatty acids. Vitamins also act as coenzymes to carry chemical groups between enzymes. For example, folic acid carries various forms of carbon group – methyl, formyl and methylene - in the cell. Although these roles in assisting enzyme reactions are vitamins' best-known function, the other vitamin functions are equally important.

Until the 1900s, vitamins were obtained solely through food intake, and changes in diet (which, for example, could occur during a particular growing season) can alter the types and amounts of vitamins ingested. Vitamins have been produced as commodity chemicals and made widely available as inexpensive pills for several decades, allowing supplementation of the dietary intake.

Занятие № 17.

1.Тема: «Vitamins»

2.Значение изучения темы – витамины необходимы человеку для нормального обмена веществ и жизнедеятельности организма. Недостаток витаминов приводит к нарушению обмена веществ и, в конечном счете, к заболеваниям, носящим название авитаминозов.

3.Цели занятия: на основе теоретических знаний и практических умений обучающийся должен уметь делать краткие записи, отвечать на вопросы, высказываться в монологе.

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4. План изучения темы:

4.1. Исходный контроль знаний. Индивидуальный устный опрос.

1.What are vitamins?

2.What we must do to be sure that our bodies get all the vitamins that need?

3.What vitamin do fresh raw fruits or vegetables contain?

4.What kind of food must you eat to get proteins?

4.2.Изучение нового материала.

1.Введение и семантизация нового лексического материала:

• Overdosage

• Harmful

• То destroy

• Rickets

• Thrombosis

• Scurvy

• Deficiency diseases

2.Ознакомительное чтение Text «Vitamins». «In nutrition and diseases» (см. приложение №1)

3.Ответить на вопросы по тексту. Задание «Make a report» - краткое

изложение в письменном виде выводов, которые студенты должны сделать на основе полученной информации.

5.Основные понятия и положения темы:

Тема: «Vitamins»

Vitamins play a very important role in human health.

Vitamin A is needed to protect eyesight and to increase resistance to infection. Vitamin В is needed to strengthen our nervous system.

Vitamin С is needed to increase resistance to infection; it helps to recover after illness. Vitamin D is needed for healthy bones and for protection against rickets.

Vitamin E is needed to improve poor blood circulation, in treatment of thrombosis. If some vitamins are lacking in the diet of people deficiency diseases may occur.

6.Задания для уяснения темы занятия, методики вида деятельности:

6.1. Вопросы для самоподготовки:

1.What are sources of vitamins?

2.What kind of substances are vitamins?

3.What diseases does the dificiency of vitamins cause?

4.What vitamins do you know?

5.Why are vitamins very important for the organism?

6.What are vitamins А, В, С characterized by?

6.2. Тестовые задания по теме.

I. Complete the following sentences.

1.Vitamin A is needed to protect eyesight and ....

2.Vitamin В is needed to strengthen ....

3.You can find vitamin С in cherry, orange, lemon and ....

4.Vitamin D is needed for healthy ... and for protection against....

5.A lot of deficiency causes ....

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6.Overdosage of some vitamins may be ... .

6.3.Ситуационные задачи по теме:

Составьте ситуации из 3-4 предложений по предложенным темам, употребив следующие слова и словосочетания:

1.Vitamins are important constituents of the living organism.

Vitamins, to be important, compounds, man, animal, to be lacking, the diet, a brearkdown, to occur, processes, metabolic, malnutrition, symptoms, result, to cause, deficiency, diseases.

2.Vitamins are unlike each other in chemical composition and function.

Vitamins, to be unlike, composition, chemical nature, to be alike, function, to be synthesized, animals, tissues, to fall into, categories, to perform, normal, matabolic, strustural.

7.Список тем по УИРС, УИР:

что такое авитаминоз и как с ним бороться?

приложение №1

In nutrition and diseases

Riboflavin (Vitamin B2)

Vitamins are essential for the normal growth and development of a multicellular organism. Using the genetic blueprint inherited from its parents, a fetus begins to develop, at the moment of conception, from the nutrients it absorbs. It requires certain vitamins and minerals to be present at certain times. These nutrients facilitate the chemical reactions that produce among other things, skin, bone, and muscle. If there is serious deficiency in one or more of these nutrients, a child may develop a deficiency disease. Even minor deficiencies may cause permanent damage.

For the most part, vitamins are obtained with food, but a few are obtained by other means. For example, microorganisms in the intestine—commonly known as "gut flora"—produce vitamin K and biotin, while one form of vitamin D is synthesized in the skin with the help of the natural ultraviolet wavelength of sunlight. Humans can produce some vitamins from precursors they consume. Examples include vitamin A, produced from beta carotene, and niacin, from the amino acid tryptophan.

Once growth and development are completed, vitamins remain essential nutrients for the healthy maintenance of the cells, tissues, and organs that make up a multicellular organism; they also enable a multicellular life form to efficiently use chemical energy provided by food it eats, and to help process the proteins, carbohydrates, and fats required for respiration.

Deficiencies

Deficiencies of vitamins are classified as either primary or secondary. A primary deficiency occurs when an organism does not get enough of the vitamin in its food. A secondary deficiency may be due to an underlying disorder that prevents or limits the absorption or use of the vitamin, due to a ―lifestyle factor‖, such as smoking, excessive alcohol consumption, or the use of medications that interfere with the absorption or use of the vitamin. People who eat a varied diet are unlikely to develop a severe primary vitamin deficiency. In contrast, restrictive diets have the potential to cause prolonged vitamin deficits, which may result in often painful and potentially deadly diseases.

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