Swallowed, Not Folded

You'll learnhow five lines of evidence show mitochondria and chloroplasts were once free-living bacteria.

Two of the organelles in your cells were once free-living bacteria. That is not a metaphor and not a guess: it is what five independent lines of evidence say when you read them together, and the nuclear envelope is the control that shows why all five are needed. Twelve short steps; press Next for each one.

12 STEPS · 6 QUICK CHECKS · INNER = THE PROKARYOTE’S, OUTER = THE HOST’S · 70S INSIDE, 80S OUTSIDE · ENDOSYMBIOSIS ≠ INFOLDING · v5

swallowed, not folded · five fingerprints it left

Before you start

What you're looking at

Two whole cells: a large flexible host, and a small free-living prokaryote with its own circular DNA, ribosomes and membrane.

The question

What happens after the host swallows the prokaryote whole, and what evidence would show it ever happened?

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