The cell. Кулагина Ж.Д. - 32 стр.

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different muscles is responsible for the movement of the body. The digestive
system includes the mouth, esophagus, stomach and intestine. It is the system in
which food is to be digested and through the walls of which food substances are
to be absorbed. The circulatory system consists of the heart and blood vessels to
circulate the blood through the body. The respiratory system includes the lungs
and trachea. It is bound to bring oxygen to the blood and take carbon dioxide
away from it. As to the excretory system it includes the kidneys which are to
eliminate waste products. The nervous system consists of brain, spinal cord and
peripheral nerves which serve to control and coordinate the activities of all the
other systems and organs.

      Ex. 18. Read text C again and write out sentences containing infinitives.
Define the functions of the infinitives.

     Ex. 19. Work in pairs. Characterize the notion “the system of organs”.
Name all the systems of organs mentioned in the text.

      Ex. 20. Give a short summary of the text.

     Ex. 21. Translate the sentences into Russian, paying attention to the
Objective with the Infinitive.

1. He wants the experiment to be done as quickly as possible. 2. Scientists have
found the nucleus to be the directing centre of some important physiological
activities of the cell. 3. Scientists consider protoplasm to be the only truly alive
part of an organism. 4. When we call a plant or an animal an organism we think
it to be organized in a definite way. 5. Scientists take the plant body to be
composed of various organs performing different functions. 6. Biologists didn’t
expect protoplasm having such a simple appearance to be so complex in its
chemical and physical organization. 7. Examining Hydra, you will find its body
to be composed of tentacles, a mouth and a body wall, each performing a
definite function. 8. Assuming an organism to be composed of parts carrying out
various functions we think all these parts to be correlated. 9. Assuming these
cells to be obtained by division we considered them identical and couldn’t
define which of them were the maternal cells and which were the daughter ones.
10. Biologists think adaptation to be the central problem of ecology as of all
biology.

      Ex. 21. Translate into English the sentences below.

1. Первая стадия митоза известна как профаза. 2. На этой стадии клетка
готовится к митозу. 3. Клетки, похожие по структуре и выполняющие одни
и те же функции, образуют ткани. 4. Все функции в организме находятся в