Unit 8 · Environmental Biology
The ozone layer and what thins it, its effects, desertification (UNCCD definition, causes and effects), and acid rain (causes and effects).
Deshapriya Senevirathne. B.Sc. (Hons) Biology Special, University of Peradeniya — graduated with a class pass. All the content and lessons in A/L Biology on Paadama are reviewed by Deshapriya Senevirathne, and the lessons are taught by him.