Theories About The Origin Of Life On Earth Flashcards
Life came from a divine being
Theory of divine creation (theory of creationism)
Life forms and everything in the universe were created through supernatural powers rather than naturalistic means
Theory of divine creation (theory of creationism)
The first life form came from an inanimate object and life could appear from non living materials
Theory of spontaneous origin (theory of abiogenesis)
Supported by John Needham, Aristotle, Epicurus and Von Helmont
Theory of spontaneous origin (theory of abiogenesis)
Tried to prove spontaneous generation by boiling broth but the duration of boiling was not enough to kill all the microbes present in the broth
John Needham
Life comes only from a living material
Theory of biogenesis
Made an experiment using maggots that arose in decaying meat; life arose from living matter like maggots from eggs
Francesco Redi
Stated that microorganisms came from other microorganisms; supporters of abiogenesis rejected his experiment because he excluded air from his sealed flask and tiny organisms from the air caused growth in the flask
Lazzaro Spallanzani
Finally disproved the theory of abiogenesis by boiling sugar solution in open flasks that had long S curved necks; organisms dont arise from spontaneous generation
Louis Pasteur
Life evolved in oceans during the period when the atmosphere was containing methane, ammonia, hydrogen gas and water (that forms amino acids)
Theory of biochemical evolution
Father of prebiotic chemistry
Stanley miller
Performed an experiment based on oparin’s hypothesis
Stanley miller
By sparking an atmosphere, hoped to generate new chemicals that would rain into the tiny ocean and react to form something; water turned into a rich broth of amino acids
Miller-Urey experiment
Flaw of the Miller-Urey experiment; composed of cyanobacteria which releases oxygen
Stromatolites
Groups of organic molecules were formed from the chemical elements in the earth’s primitive ocean and became more complex and is now capable of metabolic processes
Heterotroph theory
Proposed the heterotroph theory
A. Oparin
Can produce their own food
Autotrophs
Cannot produce their own food; feed on organic material; release carbon dioxide into the atmosphere which allow for the evolution of photosynthetic autotrophs
Heterotrophs
Hydrothermal vents provide an ideal environment with all the ingredients needed for microbial life and to emerge on early earth
Deep sea hydrothermal vent theory
Simple sulfur-containing compound that is a supposed geologic precursor of the Acetyl-CoA enzyme present in many organisms including humans
Methanethiol
Suggested that life on earth did not originate in our planet but was transported here from somewhere else in the universe
Richter
Evolution of life into higher forms is dependent on the genetics of the original microbe/s that came from space
Theory of Panspermia
Theorized that comets could carry bacteria across galaxies while simultaneously protect them from damage
Fred Hoyle and Chandra Wickramasinghe
Contains a medley of elements and compounds that can very well form the basis of life
Cosmic dust
