DP Biology (last assessment 2024)

Test builder »

Question 18N.3.SL.TZ0.a

Select a Test
Date November 2018 Marks available [Maximum mark: 1] Reference code 18N.3.SL.TZ0.a
Level SL Paper 3 Time zone TZ0
Command term State Question number a Adapted from N/A
a.
[Maximum mark: 1]
18N.3.SL.TZ0.a

A biotic index allows water pollution to be monitored without the need for a large number of chemical tests. Aquatic invertebrates are assigned pollution tolerance levels and these are used to assess water quality. The amount of each invertebrate species in the water is measured and this is used to calculate the index. The tolerance level of three invertebrate species is shown.

State which species could be found in mildly polluted water.

[1]

Markscheme

dragonfly nymph AND midge larva (Both needed)
OR
all except mayfly ✔

Syllabus sections