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Essential English for Biology Students.doc
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VII. Find synonyms among the pool of words:

Pool of words

Synonyms

1)1. multiply /2. sample /3.increase /4. specimen

2)1. image / 2. visible / 3. apparent / 4. picture

3)1.beam/2.refract/3.examine/4.bend/5.explore/6. ray

4)1.organism/2.compound/3.living thing/4. complex

VIII. Answer the following questions. Use all information given before:

  1. What are microscopes used for?

  • What types of microscopes are most commonly used today?

  • What is a compound light microscope?

  • What does the magnification of an instrument depend on?

  • How do electron microscopes differ from compound light microscopes?

  • What are the main types of electron microscopes?

  • What is the difference between the transmission electron microscope and the scanning electron microscope?

    IX. Match the sentence halves. Make complete centences:

    1.

    A microscope is used

    A.

    a light microscope or optical microscope.

    2.

    Since the 18th century many new types have been invented, of which the most commonly used today are

    B.

    they have not completely replaced light microscopes.

    3.

    The compound light microscope is also called

    C.

    in the apparent size of the object.

    4.

    The compound light microscope is also called

    D.

    the transmission electron microscope and the scanning electron microscope.

    5.

    The magnification of an instrument is the increase

    E.

    the compound light microscope and the electron microscope.

    6.

    Light microscopes can magnify objects up to

    F.

    a beam of light.

    7.

    Electron microscopes use a beam of electrons instead of

    G.

    to produce a magnified image of an object or specimen.

    8.

    There are two main types of electron microscopes:

    H.

    a light microscope or optical microscope.

    9.

    Although electron microscopes have revolutionized cell biology,

    I.

    about 1500 times without losing clarity.

    X. Read and translate the short text without any dictionary:

    Fact of life:

    A new microscope, called a scanning tunneling microscope, was invented in 1980. It measures surface features by moving a sharp probe over the object’s surface. It can achieve magnifications of 100 million, allowing scientists to view atoms on the surface of a solid. This type of microscope is likely to have a major impact on biology. Recently, it has been used to view DNA directly.

    XI. Food for thought:

    Suggest which unit should be used when calculating the diameter of the DNA molecule. Why might there be a discrepancy between the actual diameter and that estimated from the scanning tunneling micrograph?

    Have Some Fun! Biologist Jokes!

    A young college student stayed up all night studying for his zoology test the next day. As he entered the classroom, he saw ten stands with ten birds on them with a sack over each bird and only legs showing. He sat right on the front row because he wanted to do the best job possible. The professor announced that the test would be to look at each set of bird legs and give the common name, habitat, genus, species, etc.

    The student looked at each set of bird legs. They all looked the same to him. He began to get upset. He had stayed up all night studying, and now had to identify birds by their legs. The more he thought about it, the madder he got. Finally, he could stand it no longer. He went up to the professor`s desk and said: “What a stupid test! How could anyone tell the difference between birds by looking at their legs?” With that the student threw his test on the professor`s desk and walked out the door.

    The professor was surprised. The class was so big that he didn`t know every student`s name, so as the student reached the door the professor called:

    “Mister, what`s your name?” The enraged student pulled up his pant legs and said: “You guess, buddy! You guess!”

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