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BIOTECHNOLOGY

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BIOTECHNOLOGY (b) Problems with profit and waste 1. What effect does disposal of untreated sewage have on the oxygen level in the water? It lowers the oxygen levels. – PowerPoint PPT presentation

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Title: BIOTECHNOLOGY


1
BIOTECHNOLOGY
(b) Problems with profit and waste
2
1.
What effect does disposal of untreated sewage
have on the oxygen level in the water?
It lowers the oxygen levels.
3
2.
Name 4 diseases that can be spread by untreated
sewage contaminating drinking water.
  • Typhoid
  • Cholera
  • Dysentery
  • Food poisoning.

4
3.
The removal of oxygen from rivers results in
conditions.
anaerobic
5
4.
In the sewage treatment works the organic waste
is broken down by the action of
. into products that are to
the environment.
micro-organisms
decay
harmful
less
6
5.
When sewage broken down by decay micro-organisms
is it under aerobic or anaerobic conditions?
Aerobic conditions
7
6.
In what 2 ways is extra oxygen added to the
sewage to provide aerobic conditions?
  • Compressed air is added
  • Mechanical stirring

8
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
8.
Why is a range of micro-organisms essential for
sewage breakdown?
Different micro-organisms feed on different waste
materials in sewage.
10
9.
Why do we upgrade waste?
To convert it into more useful substances.
11
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
11.
Which gas is produced by fermenting organic waste?
Methane / Biogas
13
12.
Which type of fermentation fuel is produced by
fermentation of sugar cane?
Alcohol
14
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
14.
What careful lab techniques must be followed to
prevent cross contamination by micro-organisms?
  • Hands - ?
  • Benches - ?
  • Equipment -?

washed before and after the experiment.
washed down with disinfectant.
sterilised then autoclaved after experiment.
16
15.
What happens to the oxygen level in rivers when
untreated sewage is added to it?
  • The oxygen level falls

17
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
17.
What effect does sewage have on the pH of water?
  • It raises the pH ammonia gas given off makes
    the water alkaline.

19
18.
When living tissue dies, what causes it to decay?
  • The action of microbes feeding off the dead
    tissue

20
19.
During the decay process which two elements are
recycled?
  • Carbon
  • Nitrogen

21
20.
Why can alcohol and methane, both products of
fermentation be described as fuels?
Because they both burn to produce heat
22
This is the end of the questions on Problems
with Profit and Waste.
23
This is the end of the questions on Problems
with Profit and Waste.
24
This is the end of the questions on Problems
with Profit and Waste.
25
This is the end of the questions on Problems
with Profit and Waste.
26
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with Profit and Waste.
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