| Date | May 2011 | Marks available | 1 | Reference code | 11M.3.SL.TZ1.17 |
| Level | Standard level | Paper | Paper 3 | Time zone | Time zone 1 |
| Command term | State | Question number | 17 | Adapted from | N/A |
Question
State two roles of microbes in ecosystems.
Markscheme
producers
decomposers
nitrogen fixers
Two needed for one mark.
Examiners report
All parts of this question seemed to prove difficult.
Syllabus sections
Option B: Biotechnology and bioinformatics » Option B: Biotechnology and bioinformatics (Core topics) » B.3 Environmental protection
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