Animal coordination, control and homeostasisB1 Cell-level systemsB2 Scaling upB3 Organism-level systemsB4 Community-level systemsB5 Genes, inheritance and selectionB6 Global challengesBioenergeticsCell biologyCells and controlCells, tissues and organsDigestion and circulationDisease, defence and treatmentEcologyEcology and human impactEcosystems and material cyclesExchange and transport in animalsGeneticsHealth, disease and the development of medicinesHomeostasis and responseInfection and responseInheritance, variation and evolutionInheritance, variation and evolutionKey concepts in biologyNatural selection and genetic modificationNervous and hormonal controlOrganisationPlant structures and their functionsRespiration and photosynthesis