when the earth was young, its atmosphere lacked oxygen, what did the first life forms use to gain the energy?

Question

was it fermentatoin or cellular resperation...thanks

Answer 1

Microbes were the first life forms on Earth. They form the basis of the food web and are responsible for the production of most of the Earth’s oxygen. Ultimately, all life relies on these tiny, invisible creatures.

:)

Answer 2

Fermentation is a destructive process, so would not have been used by living organisms. Cellular respiration is a better alternative.

Answer 3

i guess the first life forms would use co2 like trees do, and spew out oxygen.