Biology

Guest

10 November, 12:33

Which of the following provides the best supportive evidence for the hypotheses that claim the early Earth's environment lacked free oxygen?

1) Experiments show oxygen to be very reactive and toxic to early life forms.

2) Research shows eukaryotic cells do not require oxygen for replication.

3) Reports show cyanobacteria are unable to metabolize or release oxygen.

4) Fossil records support the lack of evidence of early photosynthetic plants.