| Date | May 2017 | Marks available | 4 | Reference code | 17M.3.SL.TZ2.13 |
| Level | Standard level | Paper | Paper 3 | Time zone | Time zone 2 |
| Command term | Explain | Question number | 13 | Adapted from | N/A |
Question
Explain how microorganisms can be used in response to pollution incidents such as an oil spill.
Markscheme
a. «bioremediation» is the use of microbes to remove environmental contaminants from oil spill
b. some pollutants are metabolized/degraded by microorganisms
c. microorganisms can be eubacteria/archaeans
d. microorganisms are useful in bioremediation because they can multiply very quickly «by binary fission»
e. microorganisms can use pollutants/oil spills/crude oil as energy sources/carbon sources/electron acceptors in cellular respiration
f. eg: Pseudomonas used «in bioremediation»
g. Pseudomonas requires nutrients «such as potassium and urea» to metabolize the oil at a faster rate «so sprayed on to an oil spill to aid the bacteria in their work»
