The diversity of living beings, the diversity and multiplicity of ecosystems, and their adaptations in these different ecosystems do not facilitate the tasks for biology teachers at secondary level.In this volume, we want to guide students in Advanced Level, who are preparing for the National Exam, on the following concepts: large groups of living things, Population Genetics, Gene technology, Behavior of living things, Variation, Selection, Speciation and on the Theory of Evolution of the living world.