Biology is the study of life—a four-letter word that connects you to 4 billion years worth of family tree. The word “life” can be tricky to define, but a shared set of characteristics helps biologists identify living things. In this episode of Crash Course Biology, you’ll learn how all of life is connected, and why studying biology can help us better understand ourselves and our relationship to all living things. Chapters: Welcome to Crash Course Biology! 00:00 Life's Characteristics 2:14 Is a Virus Alive? 6:18 Life Beyond Earth 8:52 Biology and You 10:03 All Life is Connected 10:44 Review & Credits 11:59 Sources: This series was produced in collaboration with HHMI BioInteractive, committed to empowering educators and inspiring students with engaging, accessible, and quality classroom resources. Visit for more informatio
Hide player controls
Hide resume playing