Unit 4 metabolism

Pre-reading

Exercise 1. Before reading the text memorize words and word combinations.

To occur – траплятися

to proceed – продовжувати, (from) виходити, (to) переходити

to incorporate – змішувати(ся), обєднувати

to excrete – виділяти

manufacture – виробництво

to destroy – руйнувати

starch – крохмаль

acid – кислота

particularly – особливо, дуже, зокрема

significant – важливій, значний

tissue – тканина

Storage – зберігання peculiar – особливий, чудний

A-GROUP

Exercise 2. Translate the following pairs of words. Pay attention to negative prefixes.

a) organic – inorganic; comparable – incomparable; accurate – inaccurate; capable – incapable; complete – incomplete; direct – indirect;

b) liberal – illiberal; logical – illogical; legal – illegal;

c) moral – immoral; movable – immovable; modest – immodest;

d) regular – irregular; resolute – irresolute.

Exercise 3. Complete the chart.

operation – to operate

chemical – __________________

_____________ – to change

activities – __________________

respiration – __________________

______________ – to mean

_____________ – to reserve

value – __________________

_____________ – to compare

_____________ – to imitate

reaction – __________________

Exercise 4. Read and translate the text.

Metabolism

We know that life consists of complex series of chemical changes occurring in the protoplasm. As life proceeds, food and other substances are built up or broken down or changed from one form to another. Materials from the environment are absorbed and incorporated in the protoplasm. Waste materials are excreted from it, and solid substances are changed to liquids and liquids to solids. The sum of all these chemical activities is know as «metabolism».

Those metabolic processes by which complex substances are built up from simpler ones are known under the term «anabolism». The manufacture of carbohudrates from water and carbon dioxide is a good example. The breaking down of complex substances, as in respiration, is known as «catabolism». The catabolic process, by which a complex food substance is changed into a simpler form, without being completely destroyed, is known as «digestion». By means of digestion, starches and celluloses are changed to sugars; fats are changed to amino acids. This process is particularly significant as it commonly changes insoluble substances into soluble ones. Soluble substances are transported to some other part of the plant body and absorbed by the tissues, which use them.

A plant has all its reserve food material in a soluble form all the time, and it is quickly used when food is needed. But for storage purposes, the insoluble forms, such as starches, fats, and some of the proteins, are very valuable to the plant. They are also comparatively stable and do not decompose readily. Metabolic changes of materials from one form to another occur during the normal life of the plant. Sometimes changes from soluble to storage form and back again may be repeated many times before the food is actually used in metabolism.

The living parts of a plant are chemical laboratory in which many kinds of changes are taking place. When we try to imitate these reactions in our laboratories we meet some of the most difficult problems of organic chemistry. Many of these changes are so specialized that we cannot repeat them at all. We can change starch to sugar by heating it with a small amount of an acid in the presence of water, and we can further break the sugar down into water and carbon dioxide by heating it is the presence of oxygen. But the building up of sugar from water and carbon dioxide, or of starch from sugar, is still impossible.

The living cell does this work by means of special chemical agents known as «enzymes». Very little was known about enzymes until the end of the nineteenth century. Between 1890 and 1900 a series of studies, made in various places, but largely in Germany, showed us the presence of these peculiar chemical substances.

B-GROUP

Exercise 5. Give Ukrainian equivalents to the following expressions. Find them in the text and compose your own sentences with these expressions.

1) chemical changes _______________________________________

2. by means of ____________________________________________

3. environment ____________________________________________

4. to be changed ___________________________________________

5. waste materials __________________________________________

6. insoluble substance _______________________________________

7. metabolic process ________________________________________

8. soluble substance ________________________________________

9. to break down __________________________________________

10. term ________________________________________________

11. to be very valuable to ____________________________________

12. digestion ______________________________________________

C-GROUP

Exercise 6. Find in the text sentences in which predicate is used in Passive Voice and underline the predicate. Use the following verbs in the sentences of your own using Passive Voice.

Transport, decompose, build, adsorb, use, change, excrete.

Exercise 7. Write out from the text sentences with predicate in Passive Voice (not less than 10). Transform Passive into Active where it is possible. Put five types of questions to both sentences.

Exercise 8. Put missed words and word combinations, using the text “Metabolism” .

1. Life consists of complex series of ________ occurring in protoplasm.

2. In living organisms foods and other substances are built up or ______or changed from one form to another.

3. Waste materials __________ from living organisms.

4. Metabolism is the sum of all ________.

5. A good example of “anabolism” is the manufacture of _______ from water and carbon dioxide.

6. The catabolic process by which a complex food substance is changed into _______ is known as “digestion”.

7. Digestion is significant as it changes ________ into soluble substances.

8. For storage purposes, the insoluble forms such as _________ are very valuable to the plant.

9. Starches, fats and some proteins are comparatively stable and do not ________ readily.

10. Metabolic changes of materials from one form to another________ during the normal life of the plant.

Exercise 9. Translate the following sentences using the active vocabulary.

1. Процес травлення дуже важливий, оскільки завдяки йому нерозчинна речовина перетворюється на розчинну.

2. Навколишне середовище чинить значний вплив на живі організми.

3. Якщо організм функціонує нормально, продукти травлення зазвичай легко видаляються з нього.

4. Крохмаль, жири та деякі білки є відносно стійкими до розчинення.

5. Звичайно речовина знаходиться в одному з трьох станів: твердому, рідкому або газоподібному.

6. Білок являє собою сполучені амінокислоти, що включають вуглець, водень та кисень.

7. Під впливом різних факторів органічна речовина розкладається на більш прості елементи.

8. Нерозчинні форми речовини дуже цінні для рослин тому що вони є резервним поживним матеріалом.

9. Життя – це складний ряд хімічних змін у протоплазмі.

10. Вуглеводень синтезується внаслідок взаємодії води та вуглекислого газу.

D-GROUP

Exercise 10. Answer the following questions.

1. What can we call the living parts of a plant?

2. What changes take place in a chemical laboratory of a plant?

3. Can scientists imitate all chemical reactions in laboratory?

4. Can we change starch to sugar? If we can how?

5. How can we break down sugar into water & carbon dioxide?

6. Can scientists build up sugar from water & carbon dioxide or starches from sugar?

7. How does the living cell build up complex substances?

8. When were “enzymes” discovered?

9. Each enzyme can digest any substance in an organism, can not it?

10. How do temperature & freezing affect the work of enzymes?

11. What is the biological importance of enzymes?

Exercise 11. See if the following is correct, if not give the right version. Use phrases given below.

That`s right I can`t agree with it.

Exactly That`s wrong

Quite so I don`t think so.

These tiny things never grow. – That`s wrong, they eat and grow, travel and multiply.

1. Life is a complex series of chemical changes occurring in the protoplasm.

2. The absorbtion of materials from the environment & their incorporations into the protoplasm is known as metabolism.

3. Anabolism is the breaking down of complex substances into the simple one.

4. Digestion is the catabolic process by which a complex food substance is changed into a simpler form without being completely destroyed.

5. By means of digestion sugars are changed to starches.

6. Reserve food materials in plants are in a solid form.

7. For storage purposes the insoluble forms are very valuable to the plant.

Exercise 12. Find in the text the words corresponding to the following definitions.

1. Material taken into an organism and used for growth and as a source of energy.

2. Complex colloidal living substances of plant and animal cell.

3. The liquid that falls as rain and forms rivers, lakes and seas.

4. A mass of cells forming a basic structural element of an animal or plant body.

5. Substance which is present in any living matter.

Exercise 13. Look through the text and

­ Explain the process of metabolism.

– Compare the process of anabolism with that of catabolism. Give the examples.

– Show the significance for an organism of the process called digestion.

– Speak about the role of soluble forms of food materials for the plant body.

After learning all the UNITS do the following test to MODULE 5.