I. Read the text below and think of the word which best fits each space. Use only one word in each space. There is an example in (0)

Both metabolism (0) and reproduction are carried on (1)_____ cells. In eukaryotic cells the DNA lies (2)_____ the nucleus, a central structure bounded (3)_____ a membrane; in prokaryotic cells (such (4)_____ bacteria), which do (5)_____ have distinct nuclei, the DNA (6)_____ not enclosed. The proteins coded for in the DNA are synthesized (7)_____ the cytoplasm, the fluid material lying outside the nucleus (in eukaryotic cells) and (8)_____ by the cell membrane. All (9)_____ the structures required (10)_____ metabolism are contained (11)_____; thus, the cell is the unit of (12)_____ reproduction and metabolism.

II. Most of the lines in the text that follows contain an extra word. If a line is correct, put a tick (Ö ) next to the line in the answer box provided to the right. If a line has an extra word, write it in the answer box. Lines 1 and 2 are done for you as an example

1. Gene which is a unit of hereditary information that occupies a fixed 2. position on a chromosome. Genes achieve their effects by directing 3. of the synthesis of proteins. 4. Genes are composed of deoxyribonucleic acid (DNA), except for in 5. some viruses, which do have genes consisting of a closely related compound 6. called ribonucleic acid (RNA). A DNA molecule is composed of two chains 7. of nucleotides that wind about each other to resemble like a twisted ladder. 8. The sides of the ladder are made up of sugars and phosphates; the rungs 9. are being formed by bonded pairs of nitrogenous bases. 10. These bases are so adenine (A), guanine (G), cytosine (C), and thymine (T). 11. An A on one chain bonds to a T on the other (thus by forming an A–T 12. ladder rung); similarly, a C on one chain bonds to a G on the other. 13. If the bonds between the bases are broken over, the two chains 14. unwind, and free nucleotides within the cell attach themselves to the exposed 15. bases of the now-separated chains. The free nucleotides line up along with 16. each of chain according to the base-pairing rule — A bonds to T, C bonds to 17. G. This process results in the creation of two identical DNA molecules from 18. one original and is the same method by which hereditary information is 19. passed from one generation of cells to the next one.

which Ö

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VII. Fill in the spaces in the sentences below with the words from exercise V	\|	III. Fill in the spaces in the following text using a suitable form of the word given at the end of the lines. The first is given as an example

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