| Date | May 2015 | Marks available | 1 | Reference code | 15M.3.HL.TZ1.8 |
| Level | Higher level | Paper | Paper 3 | Time zone | Time zone 1 |
| Command term | List | Question number | 8 | Adapted from | N/A |
Question
List two roles for microbes in ecosystems.
Markscheme
producers/nitrogen fixers/decomposers/parasites/pathogens/nitrifiers/denitrifiers (accept other correct roles)
Award [1] for any two.
Examiners report
Many candidates could name two roles of microbes but a surprising number were only able to give one correct role for microbes in ecosystems and thus did not get the mark.
Syllabus sections
Option B: Biotechnology and bioinformatics » Option B: Biotechnology and bioinformatics (Core topics) » B.1 Microbiology: organisms in industry
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