Due to Earth's early atmosphere, what was most likely the first organisms to evolve?

1 Answer
Sep 5, 2016

The theory is that the Earth's early atmosphere did not have free Oxygen. If this theory is correct the first organisms were anaerobic .

Explanation:

One theory is that the first organisms formed in the deep sea vents where they obtained their energy from the sulfur and other high energy molecules being emitted from the under water volcanos.

This theory make sense because most modern cells and organisms depend on ATP for energy which requires the oxidation of glucose molecules. The release of energy from carbohydrates is not commonly possible without oxygen With Oxygen one glucose molecule can produce 36 ATP. Without Oxygen fermentation of glucose molecules can produce only 4 ATP