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7											8
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							11

 Check 

Across: 1. Substance that increases the rate of a chemical reaction and remains unaltered (8) 3. Enzyme-controlled breakdown of large complex molecules to simpler ones (9) 4. Complementary relationship of molecular structure allowing an enzyme to combine with one type of substrate only (11) 6. Term used to describe the state of an enzyme that has been permanently destroyed (9) 7. Building up of large complex molecules from simpler ones by an enzyme-controlled reaction (9) 9. Substance formed as the result of an enzyme acting on its substrate (7) 10. Type of organic chemical of which enqymes are composed (7) 11. Protein made by living cells that acts as a biological catalyst (6)

Down: 2. Region of an enzyme where the complementary surface of the substrate becomes attached (6,4) 5. Substance on which an enzyme acts, resulting in the formation of an end product (9) 8. Term used to describe the condition of a factor at which an enzyme works best (7)