"Diversity in the Living World" explores the vast variety of life on Earth, known as biodiversity. It highlights the interdependence between plants and animals and introduces systematic grouping based on shared physical features.

Plants are categorized into herbs, shrubs, and trees based on their height, stem type, and branching patterns. The chapter also explains the link between seeds, roots, and leaves: monocots typically have parallel venation and fibrous roots, while dicots feature reticulate venation and taproots. Animals are similarly grouped by their movement and the body parts they use, such as fins or wings.

A key focus is adaptation, the special features that allow organisms to survive in specific habitats, such as terrestrial (land) or aquatic (water) environments