A set of concise, mark scheme aligned notes for the AQA A level topic of mass transport in animals. Includes pages on: Features of transport systems Structure of Haemoglobin, explanations of oxygen dissociation curves and the Bohr shift Structure of the heart, cardiac cycle and structure of blood vessels Formation and return of tissue fluid These notes have been written by an A level Biology teacher with over 6 years experience, who is also an AQA A level examiner (Paper 3). They are concise but not too condensed and they contain mark scheme language to ensure students are able to understand the content and apply it effectively.