1 A2/A-level resources Search within results Go How ratings and recommendations work Apply Filter resourcesClear all filtersLevelClear filter A2/A-level Subject Biology Exam board WJEC TopicClear filter Human, animal and plant behaviour Human, animal and plant physiology The Collecting Duct The Kidney The Nephron Resources Revision Notes Water Reabsorption in the Collecting Duct A2/A-level, Biology Revision notes Search again