Date | May 2018 | Marks available | 6 | Reference code | 18M.3.HL.TZ2.13 |
Level | Higher level | Paper | Paper 3 | Time zone | Time zone 2 |
Command term | Discuss | Question number | 13 | Adapted from | N/A |
Question
Discuss the use of microorganisms in bioremediation.
Markscheme
a. pollutants metabolized by microorganisms
b. microorganisms useful in bioremediation because they multiply very quickly «by binary fission»
c. are varied in their metabolism/inorganic reactions
d. use pollutants as energy/carbon sources
e. use pollutants as electron acceptors «in cellular respiration»
f. bioremediation may convert heavy metals into less toxic forms «in the food chain»
g. pollution incidents can involve bioremediation combined with physical/chemical procedures
h. preferable to physical methods because of cost/time
i. preferable to chemical methods which can leave toxic residues
j. different microorganisms to be used dependent on abiotic conditions
k. one named organism