3 AS Biology resources Search within results Go How ratings and recommendations work Apply Filter resourcesClear all filtersLevelClear filter AS SubjectClear filter Biology Exam board AQA TopicClear filter Exchange and transport systems Resources Flashcards Multi-tool Revision Cards EXCHANGE AND TRANSPORT SYSTEMS AS, Biology 25 revision cards Gas Exchange Systems AS, Biology 10 flashcards Exchange and Transport Systems AS, Biology 18 flashcards Search again