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Biologists study the living world by posing questions about it and seeking science-based responses. Known as scientific method, this approach is common to other sciences as well.

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This free textbook is an OpenStax resource written to increase student access to high-quality, peer-reviewed learning materials.

Each chapter of the Study Guide begins with an outline of the text that can be used for a concise review of the text material and can also serve as a reference.

This free textbook is an OpenStax resource written to increase student access to high-quality, peer-reviewed learning materials.

This free textbook is an OpenStax resource written to increase student access to high-quality, peer-reviewed learning materials.