Apparatus and techniques
You need to have knowledge of the following pieces of apparatus and become familiar with the techniques listed.
Note: the apparatus and techniques noted below can be assessed in the question papers.
Apparatus
- beaker
- balance
- measuring cylinder
- dropper/pipette
- test tube/boiling tube
- thermometer
- funnel
- syringe
- timer/stopwatch
- Petri dish
- water bath
- colorimeter
- pulsometer
- sphygmomanometer
Techniques
- using gel electrophoresis to separate macromolecules, for example DNA fragments
- using substrate concentration or inhibitor concentration to alter reaction rates
- measuring metabolic rate using oxygen, carbon dioxide and temperature probes
- using a respirometer
- measuring pulse rate and blood pressure
- measuring body mass index
Candidates should be familiar the terms ‘control’, ‘validity’, ‘reliability’, ‘independent variable’, and ‘dependent variable’ and be able to comment on these in experimental set-up questions.
Control: a control experiment is set up exactly the same but without the treatment being applied to show the effect is due to the treatment.
Validity: all variables except the independent variable are controlled so it can be concluded that the effect is due to the independent variable.
Reliability: measurements are repeated at each level of the independent variable to reduce the effect of atypical results.
Independent variable: the variable that is changed in a scientific experiment.
Dependent variable: the variable that is measured to give results in a scientific experiment.