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"I am curious about what effect an asteroid impact, like the one that killed the dinosaurs, would have on the orbit of the earth."
  1. Question

    What is the Oparin hypothesis of the origin of life?

    In the 1920’s A.I. Oparin and J.B.S. Haldane postulated that the reducing atmosphere of early Earth (no O2) and high UV radiation would enhance the reactions that could have produced organic molecules. The 1938 Oparin hypothesis suggested that life arose through the organization of inanimate matter (organic molecules) into animated matter. He postulated that a crucial step in this process is the formation of coacervates, physical structures in which the theorized "hypercycles" of RNA and enzyme interactions could take place. The formation of coacervates occurs when colloidal solutions undergo changes in temperature, chemical, or physical environment. Coacervates have simple, persistent organization, stability in solution, and can increase in size. Most scientists in the field do not believe in this concept literally, however, Oparin correctly focused our attention on the process of self-organization of organic molecules as the central step in the transformation from inanimate to animate matter. Today, most scientists believe that this step was accomplished by protocells – membrane bound, cell-like structures that encapsulated molecules capable of performing basic cell functions such as (1) capturing energy from the environment and transforming it into chemical energy, (2) transporting nutrients and waste products between the interior of the protocell and the environment, and (3) catalyzing the chemical reactions needed for self-maintenance, growth and evolution. It was shown that such membrane bound structures can be formed from meteoritic, cometary or interstellar material. Many basic questions, however, remain unanswered.
    May 1, 2002

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