BIOL108 Chapter 25: The History of Life on Earth p.550-561, 563-567

• School: University of Alberta
• Department: Biology (Biological Sciences)
• Course: BIOL108
• Professor: Lien Luong

Document Summary

Ch 25: the history of life on earth. Conditions on early earth made the origin of life possible. Scientists hypothesize that chemical & physical processes on early earth could have produced very simple cells through 4 main stages: 1 the synthesis of small organic compounds on early earth. 1920s - oparin & haldane independently hypothesized that earth"s early atmosphere was a reducing (electron-adding) environment) in which organic compounds could have formed from simpler molecules the energy source could have been lightning & uv radiation. But some evidence suggested that the early atmosphere was neither reducing / oxidizing - made up mostly of n & co2 these neutral atmospheres have also produced organic molecules in miller-urey-type experiments. 1953 - stanley miller tested the oparin-haldane hypothesis by creating conditions similar to early stage of earth in the laboratory (known as the. His apparatus yielded several amino acids found in modern organisms.