Question

Which is the first oxygen-producing organism? ....

#Following only​

Answer 1

cyanobacteria

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Answer 2

Answer:

Cyanobacteria

Cyanobacteria, also called blue-green algae, were among the earliest organisms on Earth. These primitive bacteria produce oxygen during photosynthesis as they fix CO2 dissolved in the water. Analysis of RNA and DNA for different organisms shows that all other photosynthetic organisms derived this ability from cyanobacteria through endosymbiosis. Chloroplasts are the remnants of these engulfed cyanobacteria. Photosynthesis was invented once.

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