Ingredients of the simplest cells (prokaryotes and the sizes of their contents) -- Bigger cells (eukaryotic cells and their contents) -- Hives of industry (a survey of intermediary metabolism) -- Delights of transport (how the cell's contents are moved around) -- As if standing still (cellular homeostasis and regulatory processes) -- Internal state and gene expression (transcription and its control) -- Sustaining and changing the internal state (the interrelationship between gene expression and the cell's current composition and functional state) -- Responding to the environment (signal processing, gene expression and internal state) -- The living state (a characterization of 'life') -- Stability and change in DNA (how genes can be altered) -- The spice of life (diversity, natural selection and symbiosis) -- Curriculum vitae (an outline history of life on Earth) -- The origin of life (some major ideas and unanswered questions) -- Other worlds (the possibility of extraterrestrial life) -- Intelligent behavior and brains (the biological meaning of "intelligence") -- Human evolution (human intelligence and the question of human uniqueness) -- Cells, brains and computers: towards a characterisation of mind.