Question 18M.3.SL.TZ1.b
| Date | May 2018 | Marks available | [Maximum mark: 3] | Reference code | 18M.3.SL.TZ1.b |
| Level | SL | Paper | 3 | Time zone | TZ1 |
| Command term | Explain | Question number | b | Adapted from | N/A |
Microorganisms can be used in bioremediation of pollution, including oil spills at sea.
Explain the use of a named bacterium in bioremediation.
[3]
a. name of bacterium (genus required) and contaminating substance
b. outline of one action of (this) bacterium to remove environmental contaminants from water or soil
c. another detail of use of (this) bacterium to remove the contaminant
d. advantage e.g. environmentally damaging chemicals not required / lower cost
e. disadvantage e.g. may take longer / environmental conditions may not suit the bacterium
Full marks can only be given if a named example is given.
one example:
a. Pseudomonas (aeruginosa) to remove oil spills
b. uses crude oil for energy / breaks down crude oil
c. bacteria also need other chemicals/process may be speeded up by adding essential inorganic nutrients (phosphates/nitrates).
