Question 18M.3.HL.TZ1.11b
| Date | May 2018 | Marks available | [Maximum mark: 3] | Reference code | 18M.3.HL.TZ1.11b |
| Level | HL | Paper | 3 | Time zone | TZ1 |
| Command term | Explain | Question number | b | Adapted from | N/A |
Explain the use of a named bacterium in bioremediation.
[3]
a. (bioremediation is the) use of microorganisms to consume/break down pollutants
b. name of bacterium (genus required) and contaminating substance
c. outline one action of (this) bacterium to remove environmental contaminants from water or soil
d. another detail of use of (this) bacterium to remove the contaminant
e. advantage/disadvantage of using this bacterium
b. e.g. some Pseudomonas to remove oil spills
c. uses crude oil for energy / breaks down crude oil
d. e.g. bacteria also need other chemicals/process may be speeded up by adding essential inorganic nutrients (phosphates/nitrates)
OR
b. e.g. Pseudomonas used to remove methyl mercury
c. bacteria (Pseudomonas) degrade methyl mercury into elemental mercury and methane
d. methyl mercury is very toxic / can be biomagnified in food chain
