NK1830 NK1830
  • 11-09-2022
  • Biology
contestada

What was Earth's early atmosphere like before cyanobacteria?

Respuesta :

ogando12071 ogando12071
  • 11-09-2022

Answer:

Oxygen-free

Explanation:

Before about 2.4 billion years ago, Earth was a virtually oxygen-free environment. The appearance of cyanobacteria, or blue-green algae, changed all that. Cyanobacteria injected the atmosphere with oxygen, setting the scene for the development of complex life as we know it.

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