Edexcel 'AS' and 'A' level Biology A core practicals suitable for use with a colorimeter.

Practical 2

Investigate the vitamin C content of food and drink.

Practical 3

Investigate membrane structure, including the effect of alcohol concentration or temperature on membrane permeability.

Practical 4

Investigate the effect of enzyme and substrate concentrations on the initial rates of reactions.
There are plenty of suggested practicals with enzymes here. Our favourite, because it is simple, reliable, inexpensive and safe, uses dopa oxidase.

Practical 11

Investigate photosynthesis using isolated chloroplasts (the Hill reaction).

Practical 12

Investigate the effect of temperature on the rate of an enzyme-catalysed reaction, to include Q10.
See practical 4 (above)

Practical 16

Investigate rate of respiration practically.
SSERC have published a method which can be used with a colorimeter here