EVOLUTION
THE ORIGIN OF LIFE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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lots of oxygen
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mostly carbon dioxide with small amounts of methane, ammonia and water vapor
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mostly methane with small amounts of water vapor, carbon dioxide and ammonia
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mostly ammonia with small amounts of methane, water vapor and carbon dioxide
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Detailed explanation-1: -Based on an analysis of gases vented by modern volcanoes, it seems likely that this early atmosphere consisted mostly of water vapor (H2O) and carbon dioxide (CO2) and nitrogen gas (N2). Note that this atmosphere is very different from the one we have today.-Today, the atmosphere contains only about 0.03% CO2.
Detailed explanation-2: -(4.6 billion years ago) As Earth cooled, an atmosphere formed mainly from gases spewed from volcanoes. It included hydrogen sulfide, methane, and ten to 200 times as much carbon dioxide as today’s atmosphere. After about half a billion years, Earth’s surface cooled and solidified enough for water to collect on it.
Detailed explanation-3: -The early atmosphere contained ammonia, methane, water vapor, and carbon dioxide, but only a trace of oxygen. As the atmosphere became denser, clouds formed and rain fell. Water from rain (and perhaps also from comets and asteroids that stuck Earth) eventually formed oceans.
Detailed explanation-4: -The early atmosphere was hostile. We think the Earth’s early atmosphere was made up of mostly carbon dioxide, lots of water vapour and very small amounts of methane and ammonia. These gases made it extremely hostile. There was no oxygen, making it similar to the atmosphere of Mars and Venus today.
Detailed explanation-5: -“The amount of oxidation in the ancient micrometeorites suggests that the early atmosphere was very rich in carbon dioxide, ” said co-author David Catling, a UW professor of Earth and space sciences.