2007-01-21 16:15:27 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Biology
The atmosphere did not contain oxygen until the cyanobacteria evolved to carry on photosynthesis and make some oxygen gas.
2007-01-21 16:19:02 · answer #1 · answered by ecolink 7 · 0⤊ 0⤋
Anaerobic means that the cell does not use oxygen to make energy. There was no oxygen in the early earth's atmosphere. Oxygen was a poison.
I hope that this helps.
2007-01-22 00:19:01 · answer #2 · answered by unhrdof 3 · 0⤊ 0⤋
when the first bacteria evolved oxygen was not available in atmosphere in free state hence the earlier bacteria were considered to be anaerobic.
2007-01-22 00:57:41 · answer #3 · answered by divas 3 · 0⤊ 0⤋
Oxygen was..and is still a poison, when you have too much of it, it is a poison.
2007-01-22 00:28:44 · answer #4 · answered by nick c 1 · 0⤊ 0⤋