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No One Really Knows What a Tree Is
A TED-Ed lesson on a surprising botany puzzle: 'tree' isn't a single group of related plants but a shape that many different plants evolved on their own. Learn what makes a true tree, and how trees differ from shrubs and herbs.
How it works
- Press play to start the video.
- Videos 5 minutes or longer pause once or twice for a quick check. Get it right and you're on your way. If not, you'll see a friendly explanation and the video simply keeps going. Short videos skip the checks.
- At the end there's a 3-question test. Score 60% or more to complete the lesson, and 80% or more to master it. You can always watch again and try for a higher score.