This textbook introduces biology as an interdisciplinary science, linking physics and chemistry to biological processes that operate within the laws of thermodynamics. Based on an evolutionary narrative, the focus is on the molecular composition and the biochemistry of cells. By grounding biology in its molecular foundations, this approach reveals unifying principles underlying life's diversity and provides a conceptual framework for biological complexity. Core concepts include macromolecular structure and function, information encoding and decoding, and universal principles of energy conversion. Key FeaturesReflects a novel biology teaching approachUses evolution as the unifying frameworkIntroduces a narrative towards complexity in lifeBridges chemistry and physics to make molecular biology accessibleFocuses on bacteria and archaea as the simplest life forms to illustrate fundamental principlesProgresses from molecules through molecular interactions to cellular processesHighlights key biological concepts with summaries and reflective questionsThis textbook is designed for students seeking an integrated introduction to biology that connects molecular mechanisms to cellular structures.