AP Biology Chapter 20 Flashcards
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| 4987705921 | Phylogeny | - The evolutionary history of a species or group of species. | 0 | |
| 4987705922 | Taxonomy | - The classification and naming or organisms. | 1 | |
| 4987705923 | Binomial Nomenclature | - 2 part scientific naming format introduced by Carlos Linnaeus - 1st part- genus to which the species belongs. - 2nd part- specific epithet unique for each species. - Ex. Panthera pardus | 2 | |
| 4987705924 | Linnaean System | - Related genera. 1. Family 2. Order 3. Class 4. Phyla 5. Kingdom 6. Domain |  | 3 |
| 4987705925 | Phylogenetic tree | - Branching diagram that represents the evolutionary history of a group of organisms. - Evolutionary relationships. - Has *branch points* that indicate the divergence of 2 evolutionary lineages from a common ancestor. - Shows patterns of descent. - Sequence of branching does not indicate the absolute ages of the particular species. - You cannot assume that a taxon evolved from the taxon next to it. | 4 | |
| 4987705926 | Sister taxa | - Groups of organisms that share an immediate common ancestor. | 5 | |
| 4987705927 | Homologies | - Phenotypic and genetic similarities due to shared ancestry. - Organisms with similar morphologies and DNA sequences are more likely to be related, although this is not always the case. - More elements similar in two complex structures- organisms might be homologous. | 6 | |
| 4987705928 | Analogy | - Similarity due to convergent evolution. - Ex. Bat's wings and bird's wings are analogous. | 7 | |
| 4987705929 | Convergent Evolution | - Occurs when similar environmental pressures and natural selection produce similar (analogous) adaptations in organisms from different evolutionary lineages. | 8 | |
| 4987705930 | Homoplasies | - Analogous structures that arose independently. | 9 | |
| 4987705931 | Cladistics | - Approach to systematics where common ancestry is the primary criterion used to classify organisms. - Organisms are grouped into clades | 10 | |
| 4987705932 | Clades | - Includes an ancestral species and all of its descendants. - Nested within larger clades. | 11 | |
| 4987705933 | Monophyletic | - A taxon that forms a clade since it consists of an ancestral species and all of its descendants. | 12 | |
| 4987705934 | Paraphyletic | - A group that consists of an ancestral species and some, but not all, of its descendants. - Most recent common ancestor of all members of the group is part of the group. | 13 | |
| 4987705935 | Polyphyletic | - A group which includes taxa with different ancestors. - Most recent common ancestor is not part of the group. | 14 | |
| 4987705936 | Shared ancestral character | - A character that originated in an ancestor of the taxon. - Ex. Backbone of mammals (predates the branching of mammals from other vertebrates) | 15 | |
| 4987705937 | Shared derived character | - An evolutionary novelty unique to a clade. - Ex. Hair (not found in all mammals) | 16 | |
| 4987705938 | Outgroup | - Used when inferring phylogenies - A species or group of species from an evolutionary lineage that is known to have diverged before the lineage that includes the species were are studying. - Can be determined by morphology, paleontology, embryonic development and gene sequences. | 17 | |
| 4987705939 | Ingroup | - Used when inferring phylogenies - The species that is being studied. | 18 | |
| 4987705940 | Maximum parsimony | - Principle that says one should first investigate the simplest explanation that is consistent with the facts when finding the most accurate phylogenetic tree. - Trees base don morphology → most parsimonious tree requires the fewest evolutionary events. - Based on DNA- most parsimonious tree requires fewest base changes. | 19 | |
| 4987705941 | Molecular Clocks | - An approach for measuring the absolute time of evolutionary change based on the observation that some genes and other regions of genomes appear to evolve at constant rates. - # of nucleotide substitutions in related genes is proportional to the time that has elapsed since the genes branched from their common ancestor. - Clock speed- many mutations are neither beneficial nor detrimental. | 20 | |
| 4987705942 | From 2 Kingdoms to 3 Domains | - Taxonomists once classified all species into 2 kingdoms: plants and animals. - 5 kingdoms recognized later: monera, protista, plantae, fungi, and animalia. - Prokaryotes separated from eukaryotes in Monera. - Problem: differences between prokaryotes can be drastic. - New 3 domain system: Bacteria, archaea and eukarya. - Bacteria: consists of prokaryotes - Archaea: consists of diverse group of prokaryotes - Eukarya: organisms with a nuclei. | 21 |