The Oldest Sedimentary Rocks : Evidence For The Origin Of Life

3774 Words Aug 4th, 2015 16 Pages
1. Analysis of the oldest sedimentary rocks provides evidence for the origin of life

List the atmospheric gases believed to have existed on early earth
The atmospheric gases believed to have existed on early earth are: water vapour hydrogen methane ammonia Describe the hypothesised conditions and environment of early Earth
Early Earth is predicted to have been a very hostile environment. Due to high levels of tectonic activity, there were thought to have been many volcanic eruptions. These eruptions mixed with high temperatures caused an out-gassing of volatile molecules and initiated gases such as methane, ammonia, hydrogen, nitrogen, and carbon dioxide to exist. However, even after the introduction of these gases, oxygen was still not present. The absence of oxygen meant that the earth had no ozone layer, and was therefore exposed to large amounts of UV radiation. Early Earth was under very dangerous conditions and was unstable.

Relate the conditions on early Earth to the origin of organic molecules
Although early Earth was hostile, it provided a great environment for the production of organic molecules. Events such as lightning, volcanic eruptions, meteorites, radioactivity in the Earth’s crust, and the easy access of ultraviolet light, are thought to have provided the energy for these molecules to produce. Therefore, the conditions of early Earth were critical in the commencing of the first organic molecules.

Describe the contribution of the Murchison meteorite…
Open Document