DP Biology (last assessment 2024)
Question 20N.2.HL.TZ0.b
Date | November 2020 | Marks available | [Maximum mark: 2] | Reference code | 20N.2.HL.TZ0.b |
Level | HL | Paper | 2 | Time zone | TZ0 |
Command term | Outline | Question number | b | Adapted from | N/A |
b.
[Maximum mark: 2]
20N.2.HL.TZ0.b
Outline the role of methanogenic archaeans in the movement of carbon in ecosystems.
[2]
Markscheme
a. methane produced from organic matter;
b. in anaerobic conditions;
c. methane diffuses into atmosphere/accumulates in ground/soil;
d. oxidized/converted to carbon dioxide (in atmosphere);
Examiners report
Answers were rather polarised, with candidates either understanding the role of methanogens or stumbling round in a mire of uncertainty. Although this may seem an obscure part of biology, methanogenesis is of great significance in terms of climate change.
