Study Guide for Bio Midterm 1

Study Guide for Bio Midterm 1 - Biology (Underlines and...

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Biology (Underlines and bold) Terms Lecture 14: Origin of life (26.1, 26.2, 26.3, 26.4) 4.6 billion years ago When Earth was formed, along with the rest of the solar system Protobionts Aggregates of abiotically produced molecules surrounded by a membrane or membrane-like structure Liposomes small membrane-bounded droplets; form when lipids or other organic molecules are added to water Ribozymes RNA molecules; found to catalyze many different reactions, including self-splicing and making complementary copies of short stretches of their own sequence or other short pieces of RNA Sedimentary strata Reveal the relative ages of fossils; a layer or a series of layers of rock in ground Index fossils Similar fossils found in the same strata in different locations (EX: brachiopods) Radiometric dating Can determine the absolute ages of fossils Half-life The time it takes for ½ of the original sample to decay The three eons: Archaean (>2500 MYA) , the Proterozoic (>542 MYA) , and the Phanerozoic (<542MYA) The Phanerozoic eon is divided into three eras: The Paleozoic (541-251) , Mesozoic (251-65) , and Cenozoic (65- now) MYA The Permian extinction Killed about 96% of marine animal species and 8 out of 27 orders of insects (~260 MYA); caused by volcanic eruptions The Cretaceous extinction Doomed many marine and terrestrial organisms, notably the dinosaurs; may have been caused by a large meteor impact (~65MYA) stromatolites rocklike structures composed of many layers of bacteria and sediment Chemiosmotic Mechanism of ATP synthesis use proton gradient to generate via ATPase The theory of endosymbiosis proposes that mitochondria and plastids were formerly small prokaryotes living within larger host cells Serial endosymbiosis proposes that it happened in steps, thus explaining why there are Euks w/ mitochondria and plastids Key evidence supporting an endosymbiotic origin of mitochondria and plastids : Similarities in inner membrane structures and functions Both have their own circular DNA DNA related to prokaryotes Suggests that they were once independent organisms Snowball Earth Why larger organisms do not appear in the fossil record until several hundred million years later after eukaryotes of small algae lived 1.2 billion years ago Colonies collections of autonomously replicating cells/autonomously replicating cells Pangaea The formation of the supercontinent during the late Paleozoic era; “all earth” in Greek Subduction zone the sideways and downward movement of the edge of a plate of the earth's crust into the mantle beneath another plate Five kingdom system (by Robert Whittaker) replaced by three Archaea, Bacteria, and Eukarya 1
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domains : Lecture 16: Bacteria and Viruses (18.1, 18.2, 18.3, 18.4) Beyond their value as model systems , Viruses and bacteria have unique genetic mechanisms that are interesting in their own right model systems are frequently used by researchers to reveal broad biological principals Tobacco Mosaic Virus (TMV) How the story of viruses were discovered begins in the late 1800s
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This note was uploaded on 03/19/2008 for the course BIOL 201 taught by Professor Mitchell during the Fall '07 term at UNC.

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Study Guide for Bio Midterm 1 - Biology (Underlines and...

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