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III. Make up a list of words used to describe the structure of amoeba.
IV. Supply extended answers to the following questions.
1. Where can amoebae be found?
2. What is the body of amoeba bounded by?
3. What is the main part of the body of amoeba made of?
4. What makes it easy to distinguish the posterior end of the body of
amoeba?
5. What is there in the plasmasol at the posterior end of the body?
Text 6
I. Read the text and say what it is about.
LIFE - HISTORY OP AMOEBA
Amoeba has two different methods of reproduction which follow each other
regularly. Young amoebae which have very few granules of stored food, feed
actively and grow until they are able to split into two. In this process, known as
simple fission, they first withdraw their pseudopodia and became roughly
spherical. The nucleus divides into two halves followed by the protoplasm and two
smaller amoebae have been Termed from one. As they continue to feed and grow,
simple fission is repeated many times, fix this way the animal is prevented from
reaching a large site.
After several months (usually four to six), however, the adults show signs of
the old age; their movements become mar* sluggish, their pseudopodia are
numerous and branched, and they can no longer divide by simple fission. At this
stage the nucleus splits up into small pieces which together with a portion of
protoplasm, form tiny spherical spores not more than 1/200 mm in diameter. The
spores are set free when the old admit breaks up and dies. They resist drought
and, if the pond dries up, may be blown about, but of course they could also be
spread by ducks, moorhens and other animals. On the other hand, they can hatch
directly to form a tiny amoeba without any food granules. After feeding and
growth simple fission starts again and so the cycle goes on.
II. Make use of the notes given below, consult a dictionary about the way
the following words and word combinations are pronounced:
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