Question 2
FA student extracted DNA from strawberries.
This is the method used.
- Mash the strawberries in a plastic bag with a solution of washing-up liquid and salt.
- Filter the mixture into a test tube.
- Slowly pour ice-cold ethanol down the side of the test tube.
The Figure shows the test tube at the end of the experiment.
Figure
a.[2]
Explain why the student added washing-up liquid to the strawberries.
b.[1]
Give the reason why the student filtered the mixture.
c.[1]
Describe what the student would see at Y.
d.[2]
Explain why the student used ice-cold ethanol.
3.2 DNA and protein synthesis Questions
44 exam-style questions on Edexcel GCSE Biology 3.2 DNA and protein synthesis, covering 3.2.1 DNA structure as a polymer, 3.2.2 Genome and gene definitions, 3.2.3 Extracting DNA from fruit, 3.2.4 Base order determines protein shape, 3.2.5 Stages of protein synthesis, 3.2.6 Non-coding DNA variants affecting phenotype, and 3.2.7 Coding DNA variants affecting phenotype. Each one has a worked solution and a mark scheme showing where the marks go.