Uploaded October 2019 | Updated September 2026, 2 weeks ago

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Learn about prokaryotes, the microorganisms that make up the vast majority of living cells on Earth!

This video is part of the Bio-Dictionary for "The Explorer's Guide to Biology" (XBio for short), which is a bold re-imagining of the biology textbook for the 21st century. Visit explorebiology.org for free content that focuses on stories of scientific discovery.