Studyguide exam 1

Studyguide exam 1 - EXAM 1 Ch. 25- Phylogeny & Systematics...

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EXAM 1 Fossil Record Fossils are remnants or impressions left by organisms. Come from Sedimentary rock Biased in favor of species that existed for a long time or were widespread D irty K ing P hillip C ame O ver F or G reat S ex Domain Kingdom Phylum Class Order Family Genus Species Binomial Nomenclature- Linnaeus’s system Phylogenectics Cladistics- building of cladograms o Compares different groups from a variety of characteristics o Doesn’t necessarily reflect evolutionary history Only if the cladogram is formed by shared characteristics that are due to common ancestry (homologous) then the cladogram forms the basis of a phylogenetic tree. Homology- Similarities that are attributed to common ancestry o Analogy-Similarities that are attributable to convergent evolution o Ex: Wings in Butterflies and in Bats Phylogenetic Trees Monophyletic- Best- An ancestor and all its descendants Paraphyletic- An ancestor with some of its descendants Polyphyletic- Descendants with no common ancestor Molecular Clocks Use molecular info to estimate time since divergence Key Assumptions o Most genetic change not influenced by Natural Selection o Allows exploration of time scales too long or too short for Fossil Record o Ex: Mitochondria used to find single ancestral female to all Homo Sapiens Early Earth- developed 4.6 bya
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Volcanoes, Bombarded by Space, no liquid water Life o Prokaryotes 3.9 bya Earth cools down, liquid water, simple bacteria evolve o Eukartyotes 2.1 bya o First humans- 0.01 mya Era Age ( years ago) Events Archaen 4.6 bya Origin of Earth Paleozoic 500 mya Animal diversity increases Mesozoic 250 mya Dinosaurs rule, gymnosperms, angiosperms Cenozoic 65 mya Dinosaurs extinct, primates appear- mammals reign How do you if somethings alive? (1-4) 1. Accurate Replication 2. Response to Stimuli 3. Metabolism- use/produce Energy 4. Capable of info storage- DNA/RNA Evolution of Life Theories o Spontaneous Generation (1600-1700) o Life came from Mars via meteor/comet/etc. o Oparin-Haldance Hypothesis 1. Synthesis of Organic compounds from simple precursors 2. Formation of polymers 3. Self replicating polymers develop 4. Formation of protobiots Experiments Miller-Urey (1953) – got amino acids and Nitrogeneous bases 7/11/02- first syntheic virus created Geologic Record Half-Life—decay of radioactive isotopes 1. C 14 - fast 5730 years younger species (up to 75,000 years old) 2. U 238 - slow 4.5 b.y. half life 3. K 40 used to age sedimentary rock around fossils Continental Drift o Landmass of Earth broke apart allowing for evolutionary diversity
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This note was uploaded on 10/08/2008 for the course EBIO 1220 taught by Professor Demig-addams during the Spring '07 term at Colorado.

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Studyguide exam 1 - EXAM 1 Ch. 25- Phylogeny & Systematics...

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