A student wanted to investigate taxonomic diversity in marine phytoplankton by analysing their photosynthetic pigments. They were provided with the following materials to perform paper chromatography on a phytoplankton extract:
Describe how the student should use these materials to separate the pigments in the extract.
In the first run using solvent system A, the student resolved three distinct pigment spots. However, when they repeated the separation under identical conditions using a different solvent system, B, they resolved five distinct pigment spots. Explain the differences in the number of spots resolved by the two solvent systems.
21 exam-style questions on AQA A Level Biology Investigating diversity. Each one has a worked solution and a mark scheme showing where the marks go.