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Lyrx [107]
3 years ago
15

Which evolved first, photosynthesis or cellular respiration?

Biology
1 answer:
Readme [11.4K]3 years ago
6 0

Answer:

Because photosynthesis is a source of oxygen, it seems intuitive that photosynthesis evolved first: once enough O2 was in the air, then respiration would be able to arise in the newly oxygen-enriched atmosphere. However, some biologists have argued since the 1970's that respiration in fact evolved first.

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