IB Biology HL Unity and Diversity Concepts

Unity and Diversity connects water, molecules, cells, classification, evolution and biodiversity into evidence-based explanations of shared life patterns and biological variation.

Exam analysis

Published Concept evidence in Unity and Diversity repeatedly links cell structures, nucleic acids, organism diversity and evolution. The strongest pattern is not isolated recall, but explaining how molecular and cellular evidence supports biological unity, variation and classification.

Most tested topics

Cell structure39%
Nucleic acids28%
Evolution and speciation27%
Diversity of organisms25%
Classification and cladistics [HL only]17%
Water15%
Conservation of biodiversity12%
Origins of cells6%
Viruses [HL only]5%

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