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| 5114491166 | Fossil Record shows macroevolutionary changes including: | 1) emergence of terrestrial vertebrates 2) origins of photosynthesis 3) long-term impacts of mass extinctions | 0 | |
| 5114491167 | Possible order of Formation on Earth: | 1) Abiotic synthesis of small organic molecules 2) Joining of small molecules into macromolecules 3) Packaging of molecules into "protobionts" 4) Origin of self-replicating molecules | 1 | |
| 5114491168 | Synthesis of Organic Compounds: | 1) Early earth formed~ 4.6 bya 2) Early atmosphere~ water vapor; chemicals released by volcanic eruptions | 2 | |
| 5114491169 | Abiotic Synthesis of Macromolecules: | 1) small organic form polymers (polymerize) when they are concentrated on hot sand, clay, or rock 2) polymers formed this way are a complex mix of linked and cross-linked amino acid 3) possible that such polymers may have acted as weak catalysts for a variety of reactions on earth | 3 | |
| 5114491170 | Protobionts: | 1) aggregates of abiotically produced molecules surrounded by membrane or membrane-like structure 2) exhibit simple reproduction and metabolism 3) maintain an internal chemical environment different from external environment 4) could have formed spontaneously from abiotically produced organic compounds | 4 | |
| 5114491171 | Self-Replicating Molecules: | 1) First genetic material- probably RNA 2) Combining early protobionts with self-replicating, catalytic RNA= first life? 3) Steps toward Natural Selection: double stranded DNA, RNA taking on modern role as intermediates | 5 | |
| 5114491172 | 1920's: A.I. OParin & J.B.S. Haldane | 1) hypothesized early atmosphere= reducing environment 2) AKA electron-adding 3) necessary for forming organic molecules | 6 | |
| 5114491173 | 1953: Stanley Miller & Harold Urey | 1) Tested Oparin-Haldane Hypothesis 2) Showed that synthesis of organic molecules in a reducing atmosphere is possible | 7 | |
| 5114491174 | Liposomes | 1) small membrane-bound droplets 2) lipids (or other organic compounds) + water | 8 | |
| 5114491175 | Ribozymes | RNA molecules that can catalyze reactions like proteins; some can make complementary copies of short stretches of their own sequences or other short pieces of RNA | 9 | |
| 5114491176 | Fossil Records | 1) reveals major changes in the history of life 2) richest source of fossils are in sedimentary rock 3) biased in favor of species: existed for long time, abundant and widespread, hard parts | 10 | |
| 5114491177 | Relative Age of Fossils: | determined from rock layer (sedimentary strata) that it appears in | 11 | |
| 5114491178 | Absolute Age= Radioactive Dating | "Parent" isotope decays into a "daughter" isotope at a constant rate | 12 | |
| 5114491179 | Half-Life | 1) time required for half the parent isotope to decay 2) different for each radioactive isotope | 13 | |
| 5114491180 | Radiocarbon Dating | 1) C-14: decays into C-12; present in known concentrations in all living things 2) Death= no new C-14 incorperated 3) Time since death can be determined 4) Half-Life= 5,730 years 5) Can be used to date fossils/organic material up to 75,000 years old | 14 | |
| 5114491181 | If Fossils older than 75,000 years, ? | other isotopes with longer half-lives used (plutonium, uranium, potassium, argon) | 15 | |
| 5114491182 | Magnetism of rocks provide with dating info: | 1) iron particles in rocks align with Earth's magnetic field when the rock forms 2) magnetic field has reversed multiple times, but rocks stay aligned the same way | 16 | |
| 5114491183 | Tetrapods: | mammals, reptiles, amphibians | 17 | |
| 5114491184 | Mammal evolution has been traced based on ________ modifications, from ancestral _________ (group of reptiles) | gradual; synapsids | 18 | |
| 5114491185 | Geologic Record | 1) divided into Archean, Proterozoic, Phanerozoic eons 2) split further into eras, periods and epochs 3) major boundaries bet. geological divisions correspond to extinction events in fossil record | 19 | |
| 5114491186 | Key Events in Life's History: | 1) First Single-Celled Organisms 2) Photosynthesis and Oxygen Revolution 3) First Eukaryotes 4) Origin of Multicellularity 5) Colonization of Land | 20 | |
| 5114491187 | (1) First Single-Celled Organisms: Stromatolites | 1) rock-like structure composed of many layers of bacteria and sediment 2) 3.5 bya 3) sole inhabitants of Earth from 3.5-2.1 bya | 21 | |
| 5114491188 | (2) Photosynthesis and Oxygen Revolution: | 1) most atmospheric oxygen (O2) is of biological origin 2) O2 produced by photosynthesis reacted with dissolved iron --> iron formation (rust-like) 3) 2.7 bya --> O2 began accumulating in atmosphere and rusting iron-rich terrestrial rocks | 22 | |
| 5114491189 | (2) "Oxygen Revolution" | 1) 2.7-2.2 bya 2) posed challenge for life 3) led to cellular respiration developing 4) allowed organisms to exploit new ecosystem | 23 | |
| 5114491190 | (3) First Eukaryotes | oldest eukaryotic fossils= 2.1 bya | 24 | |
| 5114491191 | (3) Endosymbiotic Theory | proposes that mitochondria and plastids (chloroplasts and related organelles) were originally small prokaryotes living within larger prokaryotic host cells | 25 | |
| 5114491192 | (3) Endosymbiont: | 1) cell that lives within a host cell 2) undigested prey or internal parasites 3) developed mutualistic relationship --> eventually single organism | 26 | |
| 5114491193 | (3) Serial Endosymbiosis | mitochondria first, then some descendants gained chloroplasts | 27 | |
| 5114491194 | (3) Mitochondria and Plastids | 1) have similarities in their inner membrane structure and function 2) independent replication of these organelles (division similar to some pro.) 3) transcribe and translate own DNA 4) contain their own ribosomes (more similar to pro. ribo.) | 28 | |
| 5114491195 | (4) Origin of Multicellularity | 1) DNA comparisons have been used to estimate date of first common ancestor of multicellular eukaryotes (1.5 bya) 2) oldest known multicellular fossil= small algae (1.2 bya) | 29 | |
| 5114491196 | (4) "Snowball Earth" Hypothesis | 1) periods of extreme glaciation (in a glacier) 2) confined life to equitorial region region or deep-sea regions from 750-580 mya 3) Thaw of snowball corresponds to first major diversification of multicellular eukaryotes (565 mya) 4) Edicaran Biota: larger, more diverse soft-bodied organisms (565-535 mya) | 30 | |
| 5114491197 | (4) Cambrian Explosion (AKA Cambrian Period) | 1) sudden appearance of representatives of all modern phyla in the fossil record 2) 535-525 mya 3) first evidence of predator-prey interactions 4) many animal phyla appeared before Cambrian (had a long fuse) 5) 700 million- 1 billion years ago 6) DNA and Chinese Fossil evidence | 31 | |
| 5114491198 | (5) Colonization of Land | 1) First began 500 mya 2) plants & fungus likely colonized together (many mutual relationships & first land plants would have needed a vascular system; no roots/leaves) 3) Tetrapods evolved from lobe-finned fishes (365 mya) 4) Tetrapods & Arthropods are most widespread & diverse land animals | 32 | |
| 5114491199 | Continental Drift | 1) earth's continents moves slowly over underlying hot mantle 2) oceanic and continental plates can collide, separate, or slide past each other 3) Interactions bet. plates cause the formation of mountains & islands, & earthquakes 4) breakup of pangea led to allopatric speciation 5) current distributation of fossils reflects continental drift | 33 | |
| 5114491200 | Supercontinent Pangea (250 mya) | 1) less shallow water 2) colder and drier inland climate 3) changes in climate as continents moved toward and away from the poles 4) changes in ocean circulation patterns --> global cooling | 34 | |
| 5114491201 | Mass Extincton | 1) dramatic increase of the rate of extinction 2) most species that have ever lived are now extinct | 35 | |
| 5114491202 | "The Big Five" | in each one, more than 50% of Earth's species became extinct | 36 | |
| 5114491203 | End-Permian Extinction | 1) Less than 5 mya, 96% of marine animal species extinct 2) possible cause: volcanism --> global warming; decrease in oceanic oxygen | 37 | |
| 5114491204 | Cretaceous Extinction | 1) 65.5 mya; 50% marine species; many terrestrial plants and animals, including most dinosaurs 2) iridium in sedimentary rocks suggests meteorite impact~ 65 mya 3) Chiczulub crater off Mexican coast= evidence meteorite (dates to the same time) | 38 | |
| 5114491205 | Sixth mass extinction? | 1) current rate of extinction has been estimated by some scientists to be 100X-1000X the typical background rate 2) some say it caused by human actions | 39 | |
| 5114491206 | Consequences of mass extinction: | 1) alter ecological communities & available niches 2) can take 5-100 my for diversity to recover 3) can pave the way for adaptive radiations | 40 | |
| 5114491207 | Adaptative Radiations | evolution of diversity adapted species from a common ancestor upon introduction to new environmental opprotunites | 41 | |
| 5114491208 | Worldwide adaptive radiations: | 1) mammals underwent adaptive radiation after extinction of terrestrial dinosaurs 2) other notable radiations include: Photosynthetic prokaryotes, large predators in cambrian, land plants, Insects, Tetrapods | 42 | |
| 5114491209 | Regional adaptive radiations: | can occur when organisms colonize new environments with little competition | 43 | |
| 5114491210 | Heterochrony | 1) can have significant impact on body shape 2) Ex: contrasting shapes of human and chimpanzee skulls are the result of small changes in relative 3) can alter the timing of reproductive development relative to the development of non reproductive organs | 44 | |
| 5114491211 | Paedomorphosis | 1) rate of reproductive development accelerates compared with somatic development 2) sexually mature species may retain body features that were juvenile structures in ancestral species | 45 | |
| 5114491212 | Changes in Spatial Pattern | substantial evolutionary change can also result from alterations in genes that control the placement and organization of body parts (Homeotic Genes) | 46 | |
| 5114491213 | Evolution of Development | 1) Tremendous increase in diversity during the Cambrian explosion is a puzzle 2) Developmental genes may play an especially important role 3) Changes developmental genes can result in new morphological forms | 47 | |
| 5114491214 | Changes in Gene Regulation | 1) Ex: three-spine sticklebacks in lakes have fewer spines than their marine relatives 2) Same gene sequence, different gene expression | 48 | |
| 5114491215 | Evolution is like tinkering- | process in which new forms arise by the slight modification of existing forms | 49 | |
| 5114491216 | Complex structures usually evolve in many _______ stages from previously __________ structures. (apparently happened independently) | small; existing | 50 | |
| 5114491217 | Some structures evolve in one context but become co-opted for a different ___________. | function | 51 |
