Class 12 Zoology

Class 12 Zoology is the most fact-dense paper in the science group, and the one-mark section is where that density shows. The Samacheer Kalvi syllabus runs through reproduction in organisms, human reproduction, reproductive health, the principles of inheritance and variation, molecular genetics, evolution, human health and diseases, applied biology, and organisms and environment. Names of hormones, diseases, techniques and scientists carry marks on their own, and the diagrams matter as much as the text. The articles below organise each unit into what has to be recalled exactly, what only has to be recognised, and which questions the board has asked more than once.