1. W. McConnell 2004 Kinross High School BIOTECHNOLOGY ( b ) Problems with profit and waste

2. W. McConnell 2004 Kinross High School 1. What effect does disposal of untreated sewage have on the oxygen level in the water? It lowers the oxygen levels.

3. W. McConnell 2004 Kinross High School 2. Name 4 diseases that can be spread by untreated sewage contaminating drinking water. Typhoid Cholera Dysentery Food poisoning.

4. W. McConnell 2004 Kinross High School 3. The removal of oxygen from rivers results in ……………… conditions. anaerobic

5. W. McConnell 2004 Kinross High School 4. In the sewage treatment works the organic waste is broken down by the action of ………… ………………….… into products that are …… …………… to the environment. harmfulless micro-organismsdecay

6. W. McConnell 2004 Kinross High School 5. When sewage broken down by decay micro- organisms is it under aerobic or anaerobic conditions? Aerobic conditions

7. W. McConnell 2004 Kinross High School 6. In what 2 ways is extra oxygen added to the sewage to provide aerobic conditions? Compressed air is added Mechanical stirring

8. W. McConnell 2004 Kinross High School 7. Why is it important that some sewage bacteria respire anaerobically? So that the sewage can be completely broken down. Aerobic bacteria can only break down some of the waste matter.

9. W. McConnell 2004 Kinross High School 8. Why is a range of micro-organisms essential for sewage breakdown? Different micro-organisms feed on different waste materials in sewage.

10. W. McConnell 2004 Kinross High School 9. Why do we upgrade waste? To convert it into more useful substances.

11. W. McConnell 2004 Kinross High School 10. Give 2 examples of more useful substances which are produced when waste is upgraded. Increased levels of protein in the waste Increased energy content of the waste

12. W. McConnell 2004 Kinross High School 11. Which gas is produced by fermenting organic waste? Methane / Biogas

13. W. McConnell 2004 Kinross High School 12. Which type of fermentation fuel is produced by fermentation of sugar cane? Alcohol

14. W. McConnell 2004 Kinross High School 13. What are the advantages of using fermentation fuels rather than fossil fuels? Harmless to the environment Easy to obtain Cheap to obtain Renewable

15. W. McConnell 2004 Kinross High School 14. What careful lab techniques must be followed to prevent cross contamination by micro-organisms? Hands - ? Benches - ? Equipment -? washed before and after the experiment. sterilised then autoclaved after experiment. washed down with disinfectant.

16. W. McConnell 2004 Kinross High School 15. What happens to the oxygen level in rivers when untreated sewage is added to it? The oxygen level falls

17. W. McConnell 2004 Kinross High School 16. Why does the oxygen level in a river fall if untreated sewage is added to it? Bacteria feed on the raw sewage and use up the oxygen from the water.

18. W. McConnell 2004 Kinross High School 17. What effect does sewage have on the pH of water? It raises the pH – ammonia gas given off makes the water alkaline.

19. W. McConnell 2004 Kinross High School 18. When living tissue dies, what causes it to decay? The action of microbes feeding off the dead tissue

20. W. McConnell 2004 Kinross High School 19. During the decay process which two elements are recycled? Carbon Nitrogen

21. W. McConnell 2004 Kinross High School 20. Why can alcohol and methane, both products of fermentation be described as fuels? Because they both burn to produce heat

22. W. McConnell 2004 Kinross High School This is the end of the questions on ‘Problems with Profit and Waste’.

23. W. McConnell 2004 Kinross High School This is the end of the questions on ‘Problems with Profit and Waste’.

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