99% of life needs oxygen to survive, so how did all life come about without plant life to covert carbon dioxide to oxygen? Plant life could not have came from a chemical pool of bacteria when there DNA and cell make up are completely different.
2007-06-11 12:49:55 · 6 answers · asked by Anonymous in Science & Mathematics ➔ Biology
You have to be careful pulling a statistic like "99% of life needs oxygen to survive" out of a hat. (Unless you have some source that backs it up.)
It is simply NOT true. (Following two statements are from my first source below.)
"Overall the combined weight of biological material -- animals, plants, insects, crops, bacteria, and so on -- has been estimated in one source at about 75 billion tons."
"Another source puts the amount of oceanic cyanobacteria at 44 billion tons, a huge chunk of the earth's total living matter."
That's TODAY. And that's only cyanobacteria .. it does not include the huge number of other bacteria that are able to survive without oxygen.
I bring up cyanobacteria because they (not plants) are probably responsible for the earth's free oxygen in the atmosphere.
Of the 4.6 billion years the earth has been here, about 3 billion years was with nothing but single-celled anaerobic bacteria. We multi-cellular creatures are newcomers within the last billion years, and still represent a tiny fraction of the total number of organisms on the planet.
2007-06-11 15:39:47 · answer #1 · answered by secretsauce 7 · 1⤊ 0⤋
There are not now, and never have been, any organisms which can live with no oxygen at all, although there are quite a few (called anaerobes) which don't need free oxygen (and may be killed by it). The original life on this planet did not require free oxygen, which is just as well because there wasn't any. Nor was it based on DNA; DNA life arose from RNA life, which probably arose from something else (and we have no idea what). The original atmosphere of carbon dioxide, methane, and nitrogen was converted to the present oxygen-rich atmosphere by photosynthetic life about 2.5 billion years ago -- after two billion years of evolution.
2007-06-11 13:15:48 · answer #2 · answered by Anonymous · 0⤊ 0⤋
a million GOD. 2 food. 3 Water. 4 easy. 5 Darkness. 6 Air. 7 workout. 8 relax. 9 actual senses. 10 human beings being around. 11 good solutions to questions of little fee. 12 Values for others rights. 13 Morals to stay by. 14 actuality in meaning of all issues. 15 self well worth. Now do I win the cookie or no longer?
2017-01-06 08:14:31 · answer #3 · answered by barakat 4 · 0⤊ 0⤋
Bacteroides fragilis
Bacteroides melaninogenicus
Peptostreptococcus anaerobius
Clostridium botulinum
Clostridium tetani
Clostridium perfringens
Clostridium difficile
Fusobacterium nucleatum
Fusobacterium necrophorum
Actinomyces israelii
Methanogenium cariaci
Methanococcus thermolithotrophicus
Methanococcus maripaludis C5
Methanococcus jannaschii
Methanopyrus kandleri
Methanobacterium thermoautotrophicum
Methanoculleus marisnigri JR1
Methanosaeta thermophila
Methanosarcina acetivorans
Methanococcoides burtonii
2007-06-11 13:45:57 · answer #4 · answered by ecolink 7 · 2⤊ 0⤋
Plenty of bacteria are capable of being anaerobic (living without oxygen).
Streptococcus pyogenes
Clostridium spp, ie Clostridium botulinum, Clostridium tetani
Peptostreptococcus
Bacteroides spp
Campylobacter
Lactobacillus (inclusive of those in yakult/vitagen)
Fusobacterium
Listeria
Prevotella
Archaea bacteria (almost, if not all, archaebacteria are capable of living without oxygen)
2007-06-11 13:21:00 · answer #5 · answered by Anonymous · 1⤊ 1⤋
yeast,oricifera,clostridium
2015-07-17 20:47:59 · answer #6 · answered by Vishal 1 · 1⤊ 0⤋