Panspermia Hypothesis

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There is an overwhelming amount of support for theories on the origin of life. Although each theory differs to one another, all proposed theories imply that life has evolved from single-celled microorganisms to the complex multicellular life forms that have existed over millions of years.
The first hypothesis I am evaluating is the Panspermia hypothesis. Panspermia, from Ancient Greek is defined as (pan) meaning ‘all’, and (sperma) meaning ‘seeds’. It is the hypothesis that states life exists all throughout the Universe, and life is propagated throughout space from location to location via meteoroids, comets (Wickramasinghe, 2011), and planetoids (Rampelotto, 2010). To some people, this is how life on Earth originated.
Panspermia is a theory
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Some proposed that evidence for Panspermia seems weak, and there is the view of Crick (Crick, 1993) who suggests that the implausibility of the RNA world may imply that life that we know of did not originate on our planet, but instead on a planet where there might have been conditions that were selectively favourable for the evolution of RNA. Implications of this are that it is much less adverse for RNA to have existed on a more favourable planet than existing on Earth at a time which would not have favoured the origin of the RNA world (Crick, 1993).
The second hypothesis that I will be evaluating is the Oparin-Haldane hypothesis, a theory put forward separately by biochemists Alexander Oparin and J. B. S.Haldane who both subsequently released independent papers. Their theories stated that life started to appear in the oceans during a time of atmospheric reduction. According to the theory, organic compounds were synthesis nonbiologically via ultraviolet light, made possible due to the lack of an ozone shield, allowing for light to penetrate the upper layers of the ocean surface (Haldane, 1929., Oparin,
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The LCHF provides insights into past mantle geochemistry and presents a better understanding of the chemical compositions that existed during the evolutionary transitioning, from geochemical processes to biochemical processes (Baker & German, 2004). However, there is a reason to doubt the origin of life from hydrothermal vents. One of the main arguments against the origin of life from the deep sea, is the fact that so many macromolecules are found in biology. Molecules such as DNA, RNA, proteins and lipids are all polymers and form via condensation reactions – a wet environment is required for molecules to mix, but water then needs to be removed in order to form a polymer (Da Silva,
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