Oxygen was one of the original gases abundant in Earth's atmosphere before the evolution of life.

Question

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Oxygen was not present in the Earth's atmosphere before the evolution of life. It was first produced by photosynthetic organisms around 2.4 billion years ago. Initially, the atmosphere contained mainly nitrogen, carbon dioxide, and water vapor. Oxygen gradually increased in the atmosphere due to photosynthesis, providing a suitable environment for more complex forms of life to evolve.

Oxygen Was One of the Original Gases Abundant in Earth's