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Cards In This Set
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Continental drift
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The movement of continents in geological times; earth's crust and part of its upper mantle are divided into a series of plates that move laterally over the glove; by moving land-masses on and off the poles, continental drift has helped change the climate; has brought about the separation and mixing of living populations
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Source of life's raw materials: above, beyond or below hypotheses
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Methane, hydrogen, and ammonia provided by the atmosphere (above); outer space as the source of fully formed building blocks like amino acids, delivered by meteorites and comets- unlikely b/c it is unlikely that "seeding" could have brought a sufficient quantity of organic materials to get life going (beyond); from methane and hydrogen sulfide that gush out from deep-sea vents on the floors of the oceans- the very oldest organisms on Earth may have been heat-tolerant organisms, but scalding temperatures would have obliterated any early self-replicating molecules which were bound to be fragile- a much more likely home are sheltered stretches of ancient ocean beaches, where tides and shoreline rocks would have sorted organic materials and been joined by fresh materials delivered by ocean waves (below)
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This single molecule performed both the DNA and enzyme roles, enabling the first living things to reproduce themselves
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RNA
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Rybozymes
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Enzymes that are composed of RNA instead of protein; can encode information and act as enzymes; provide critical evidence of RNA's role in early life
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Life is said to have begun when
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RNA's precursor began to carry out variable self-replication; it is important that these molecules were able to vary from one another because only then could natural selection occur
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The three domains of life are...
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Bacteria, Archaea, and Eukarya
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The four kingdoms within Eukarya are
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Protista, Plantae, Animalia, and Fungi
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Bacteria and archaea are made up strictly of...
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Single-celled microbes (are microscopic) and lack a nucleus (are prokaryotic)
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Protists
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Mostly microscopic and water-dwelling organisms; the term refers to many evolutionary lines
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Universal ancestor
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The organism or group of organisms that gave rise to all current life
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Stomatolites
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Internal patterns found in rock deposits of Western Australia from 3.4 billion years ago that are so complex that it's likely they could only have been created by living organisms
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Photosynthesis began in bacteria by at least 3.4 billion years ago, making available a massive quantity of energy-rich food
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Cyanobacteria were the first organisms to produce _______ as a by-product of photosynthesis
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Oxygen
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Organisms that obtain their energy _________ can extract a great deal more energy from a given quantity than others that lack this capacity
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Aerobically; oxygen-aided
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Ancient bacteria that could metabolize oxygen took up residence in early eukaryotic cells and eventually struck up a ________ _________ relationship with them
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Mutually beneficial
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