Cyanobacteria Are Believed to Generate the Majority of Oxygen Gas

question 29

Multiple Choice

Cyanobacteria are believed to generate the majority of oxygen gas in Earth's atmosphere. What allows them to produce oxygen?

• A) photosynthesis in which H₂S is the electron source
• B) photosynthesis in which water photolysis produces H⁺, e^-, and O₂
• C) bacteriorhodopsin-based photosynthesis
• D) all of the above
• E) none of the above

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