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3.24 Use the Gerund of the verbs in brackets.

  1. Students began (read) this article two hours ago.

  2. Nowadays scientists are working out methods for (utilize) atomic energy for general use in peaceful purposes.

  3. Upon (be excited), muscles contract to produce movements, and gland cells pour forth the secretions previously synthesized within them.

  4. The catabolic process by which a complex food substance is changed into a simpler form without (be) completely destroyed is known as digestion.

  5. A catalyst is a substance that accelerates a chemical change without itself (become) one of the products of the reaction or otherwise (alter) the end achieved.

  6. Water is an essential plant nutrient. (Apply) irrigation water in arid areas differs very little in principle from (apply) fertilizer in humid areas.

3.25 Complete the sentences using the Gerund.

1. They succeeded in …

2. We are interested in …

3. It is no use …

4. This experiment is worth …

5. The students admitted …

6. We go on …

7. The biologists postponed …

8. They agreed to …

9. The scientists were capable of …

10. The lectures wanted to be informed of …

UNIT 4

The Cell

Reading and Speaking

4.1 You are going to read the text, check the meaning and pronunciation of the words in the dictionary if necessary

Protoplasmatic, connection, significance, tool, division, slice, tier, monk, to convey, mold, successor, observation, generalization, outcome, to precede, to state, to arise.

4.2 State the part of speech of the following words. Translate them.

To signify, significance, significant.

To compose, to decompose, composer, composition, decomposition.

To connect, connection, connective.

To organize, organizer, organization.

To arrange, arrangement.

To generalize, generalization, generality, general.

Concept, conception.

To actualize, actuality, actual, actually.

Attention, attentive, attentively.

To brief, brief, brief, briefly.

Accurate, accuracy, accurately.

Divide, division.

Exist, existence, existing, pre-existing.

4.3 Entitle the text, make up its plan, using sentences from the paragraphs or putting questions to each paragraph.

The unit of protoplasmatic organization is the cell. The word “cell” is not a very good choice in this connection , but it has significance in the history of biology. The name was given by Robert Hooke, one of the first scientists having used a newly developed biological tool, the microscope, to the tiny divisions that he saw in thin slices of cork. The cork slice, through his microscope, appeared to be made up of many small compartments, arranged in rows, and reminded him of the tiers of monks' cells in English monasteries. He therefore called each compartment a cell and the name has survived, although it does not accurately convey the picture of a living unit. What Hooke actually saw in the nonliving wall which had once surrounded the living protoplasm, was not the protoplasm itself. His microscopic studies of some other materials, such as feathers, fish scales, molds, snow crystals and fabrics, brought him closer to the sight of living cells but not close enough to see the living substance.

Observations of the classical microscopists and those of their successors individual cells as parts of organisms, both plant and animal, led to one of greatest and for a time most useful of biological generalizations, the cell theory. This concept was first brought to general attention in 1838.

It was a natural outcome of the many observations that had been made during the early part of the nineteenth and the preceding centuries. Briefly, it states that all organisms are composed of cells or of a single cell and that all cells, and hence all organisms, arise from the division of pre-existing cells. This theory was to biology, at that stage of its development, what Dalton's atomic theory was to chemistry.