Key term for Edexcel GCSE Biology, used in Photosynthesis.
A relative unit of measurement used to compare data points when absolute values (such as lux) are not required.
Arbitrary units (au) appears in Edexcel GCSE Biology revision content for Plant Structures and Functions, especially Photosynthesis and Inverse Square Law.
Create a free account to access Edexcel GCSE Biology revision notes, track progress, and practise related key terms.
