The cell. Кулагина Ж.Д. - 11 стр.

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the ordinary activities of a plant may be carried out perfectly well in the entire
absence of the usual cellular organisation.

       Ex. 12. Read text A again and collect the sentences telling about the role
of the nucleus in the function of the cell.

      Ex. 13. Answer the questions.

1. What do we call a cell? 2. What are the main parts of it? 3. What form has the
nucleus? 4. What is it bounded by? 5. What is the role of the nucleus in the
physiological activities of the cell? 6. What are the chemical characteristics of
the nucleus. 7. How many nuclei are there in an ordinary cell?

      Ex. 14. Give a brief summary of the text.

      Ex. 15. Use the Active in the sentences below.

1. Living processes are carried out by certain organs. 2. The cell wall is
perforated by many small openings. 3. Animal cells are bounded by a thin,
delicate, semi-permeable membrane. 4. The rate of the cytoplasmic flow is
affected by temperature and other environmental conditions. 5. Some vital
activities of the cell are performed by the cytoplasm itself.

      Ex.16. Analyse and translate the following sentences. Enclose Participle
constructions in brackets.

Model: Animal cells are bounded by a thin membrane seen only under the
       electron microscope.
       Animal cells are bounded by a thin membrane (seen only under the
       electron microscope).
       1. Everything entering or leaving the cell must pass through the plasma
and vacuolar membrane. 2. From the point of view of the kinds of organisms
studied there are two main divisions in biology-botany and zoology. 3.
Examining a piece of a plant under a microscope, you will see its cellular
structure. 4. The cell wall although formed by protoplasm is not a part of the
living material. 5. Protoplasm when examined under a microscope is a thin
granular substance. 6. Ecologic problems spoken about at the conference are of
vital importance. 7. The symposium attended by many well-known scientists
discussed many of the biological problems. 8. If watered plants grow well. 9.
While dividing the cell goes through several stages. 10. Having been developed
the nucleus divides.