Задания

1. Ответьте на вопросы:

1. What substances are known as carbohydrates? 2. What is sugar responsible for? 3. How is starch built? 4. What is the role of cellulose? 5. What do you know about organic acids? 6. What foods are high in carbohydrates?

2. Укажите номера пропущенных предлогов; переведите данные предложения на русский язык.

1. Food is considered high or low ... carbohydrates according ... their amount to its total weight. 2. To meet the requirements of the body ... energy food must be high ... carbohydrates, proteins, vitamins and minerals. 3. ... means of these experiments we shall define the amount … starch in this substance. 4. Starch is a carbohydrate more complex ... nature than any of sugars. 5. A number ... food constituents have a part ... stimulating and regulating body processes. 6. The utilization of organic acids in the body for energy is similar ... that of starches and sugars. 7. Any kind of sugar is responsible ... a sweet taste of certain foods.

l. by 2. for 3. in 4. to 5. of

3.Переведите на русский язык данные словосочетания, учитывая много­значность слов «part» и «mean».

• part часть, доля; участие/доля/ в работе; роль

1. parts of a body, the part of grain, parts of the plant;

2. to take part in research, to have a part in producing sugar;

3. to play a significant part in the food industry; they took an active part in the investigation.

• mean I. значить, иметь значение 2.средний

means средство/а, способ

1. the term "sugar" to most people means cane or beet sugar; the word "vitamin" means "very important for life"; the word "enzyme" comes from the Greek word meaning "in yeast";

2. mean consumption of sugar; mean daily need for energy; mean level;

3. means of production; means of living; means of analysis; an effective means;

by means of synthesis; by means of heating; by no means; by all means.

«Sugar and starch»

1. Прочитайте текст и составьте план на русском языке.

2. Кратко изложите текст на английском языке, пользуясь планом.

Among common carbohydrates are sugar and starch. Although these substances differ widely from one another in properties and constitution, they show a very definite point of resemblance. They are all composed of carbon, hydrogen and oxygen, and the hydrogen and oxygen are always in the sane ratio to one another as in water, i.e.¹, two of hydrogen to one of oxygen. The name, therefore, of carbohydrates was given because these compounds seemed to be built up of carbon and water in different proportions. Thus glucose, as sugar, has a formula C₆H₁₂O₆ – which might be represented as 6C+6H₂O. It may be pointed out that this last method of representation is only referred to for the purpose of showing how the name arose.

There is hardly a plant that does not contain either sugar or starch or cellulose or even all the three of them. The sugar and starches are among our most common foods, and the celluloses though not useful as a food, are found the main constituents of wood, paper, cotton and other fibres or fibrous materials.

Our ordinary everyday life leads us to think that there is only one sugar, viz²., that we use as a sweetening agent for tea. In fact there are many sugars, they are glucose (so called dextrose or grape-sugar), fructose (also called levulose) and galactose.

Glucose or grape-sugar is found in large quantities in grapes. When these are dried in the sun to form resins, the glucose in the juice separates out as hard brown nodules³. It is frequently found mixed with fructose in the juice of fruits, in the roots and leaves of plants and in honey. It can also be obtained from cane sugar and starch. Glucose is soluble in about its own weight of water and is not so sweet as ordinary cane sugar.

It readily ferments with yeast and yields principally alcohol and carbon dioxide.

Fructose occurs with glucose in the juice of sweet fruits and in honey. It is more soluble in water than glucose, and is about as sweet as the latter. It ferments with yeast but not as rapidly as glucose.

1. id est – то есть

2. viz.=videlicet – а именно

3. nodules – (зд.) масса=комочки