Question

Question #cbfa0

Answer 1

If you mean endosymbiotic theory then it's basically the evolution of cells.

Explanation:

It's basically suggesting that a mitochondria and plastids in eukaryotic cells were once independent prokaryotic cells. And that there were 3 prokaryotes which different functions such as aerobic respiration and converting energy, photosynthesis and one that was incapable of doing either of these processes (lazy cell).
The lazy cell engulfed the respiration cell, it was then able to make useful energy. When it engulfed the photosynthesis cell, it was then able to convert energy from the sun into stored chemical energy.
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