Question

Why are cyanobacteria important to early Earth?

A. Cyanobacteria stopped the formation of rust in Earth's crust
B. Cyanobacteria preceded the first photosynthetic organisms
C. Cyanobacteria are the first photosynthetic organisms
D. Cyanobacteria produced iron in Earth's crust

Answer 1

Cyanobacteria played an important role in the evolution of Early Earth and the biosphere. They are responsible for the oxygenation of the atmosphere and oceans since the Great Oxidation Event around 2.4 Ga, debatably earlier.

Step-by-step explanation:

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