What component of earth’s atmosphere exists entirely as a result of photosynthesis? oxygen gas water vapor nitrogen gas carbon dioxide gas

Oxygen gas is a component of Earth's atmosphere and exists entirely as a result of photosynthesis.

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Davinia.

Oxygen Gas

Explanation:

The plants and phytoplanktons performs the process of photosynthesis that adds oxygen into the environment.

The plants use carbon dioxide from atmosphere, water and nutrients from the soil to synthesize glucose in the presence of sunlight.

This process releases oxygen back into the atmosphere as it is a by product of this process.

answer; ///i believe the correct answer is (aids) acquired immune deficiency syndrome;

the darker peppered moth species were favored due to the fact that the industrial revolution had made all the nearby trees a darker color instead of white.