The cell. Кулагина Ж.Д. - 21 стр.

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       In the second stage called the metaphase the chromosomes arrange
themselves in the equatorial plane of the cell in the form of a star.
       The third stage of mitosis, known as the anaphase, begins when the
chromosomes, already split, separate. At this stage the space between the
chromosomes becomes greater and greater. The threads of the spindle extending
between the centrioles become shorter, and the two halves of each chromosome
gradually migrate to the poles of the cell.
       The forth and final stage of division is called telophase. During it the
chromosomes uncoil, the nucleolus reappears and nuclear membranes surround
each group of daughter chromosomes. Thus an exact division of the material of
each chromosome is made between the daughter nuclei. In the cytoplasm of
each daughter cell a new division of the centrioles takes place and a membrane
forms between the two cells obtained as a result of the division. Such daughter
cell is smaller than the maternal one, but gradually grows and obtains the
dimensions and shape typical of the cells concerned.

      Ex.10. Answer the following questions:

1. Is reproduction an inherent property of the living cell? 2. How many cells are
obtained in the result of the reproduction? 3. Are the newly obtained cells
identical or different from the maternal ones? 4. What processes does the cell go
through while dividing? 5. When does the cell division begin? 6. What does the
process of division begin with? 7. What do scientists call this first stage of
division? 8. In what way do the chromosomes arrange themselves in the second
stage of division? 9. When does the final separation of the chromosomes take
place? 10. What happens to the chromosomes at the final stage of division? 11.
Does the division of the centrioles also take place? 12. Gradually the daughter
cells attain the dimensions and shape of the typical cell, don't they?

      Ex. 11. Using fig. 2, describe in writing the process of cell division. Use
the words and phrases given in text A and in ex. 13, Unit III.

      Ex. 12. Use the words given below to make up new word combinations
with "due to", "in addition to", "to depend on".

      Model: a) due to optimal temperature;
            b) in addition to optimal temperature;
            c) depend on optimal temperature.

      This first stage, daughter chromosome, this inherent property, this
surprising capacity, this function, such coordination of functions, growth and
reproduction, the increase in size, the sensitivity of an organism to outer
changes, the nucleus membrane, the maternal cell, the differentiation of the