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| 5318099334 | homologous structures | Structures that come from the same ancestor...have a common origin and reflect a common ancestry. |  | 0 |
| 5318099335 | vestigial structures | remnants of features that served important functions in the the organism's ancestors |  | 1 |
| 5318099336 | convergent evolution | the independent evolution of similar features in different lineages |  | 2 |
| 5318099337 | gene pool | the aggregate of all of the alleles for all of the loci in individuals in a population |  | 3 |
| 5318099338 | natural selection | a process in which organisms with certain inherited characteristics are more likely to survive and reproduce than are organisms with other characteristics |  | 4 |
| 5318099339 | founder effect | when a individuals become isolated from a larger population, this smaller group may establish a new population whose gene pool differs from the source population |  | 5 |
| 5318099340 | bottleneck effect | when there is a severe drop in population size, certain alleles may be overrepresented among the survivors, others may be underrepresented, and some may be absent altogether |  | 6 |
| 5318099341 | gene flow | the transfer of alleles into or out of a population due to the movement of fertile individuals or their gametes. (Ex. pollen from one valley can be carried by the wind across a mountain to another valley.) | 7 | |
| 5318099342 | directional selection | when conditions favor individuals exhibiting one extreme of a phenotypic range, thereby shifting the frequency curve for the phenotypic character in one direction or the other |  | 8 |
| 5318099343 | disruptive selection | Increases the extreme types in a population at the expense of intermediate forms. What may result is called balanced polymorphism, one population divided into two distinct types. Over great lengths of time, disruptive selection may result in the formation of two new species. |  | 9 |
| 5318099344 | stabilizing selection | Sometimes called purifying selection, eliminates the extremes and favors the more common intermediate forms. Many mutant forms are weeded out in this way. |  | 10 |
| 5318099345 | sexual selection | Selection based on variation in secondary sexual characteristics related to competing for and attracting mates. In the males, antlers, strength are the result of sexual selection. Difference in APPEARANCE between males and females are known and sexual dimorphism. |  | 11 |
| 5318099346 | sexual dimorphism | marked differences between the two sexes in secondary sexual characteristics, which are not directly associated with reproduction or survival (differences in size, color, ornamentation, and behavior) |  | 12 |
| 5318099347 | diploidy | the state of being diploid, that is having two sets of chromosomes | 13 | |
| 5318099348 | heterozygote advantage | when individuals who are heterozygous at a particular locus have greater fitness than do both kind of homozygous | 14 | |
| 5318099349 | frequency-dependent selection | fitness of a phenotype declines if it becomes too common in the population | 15 | |
| 5318099350 | speciation | the process by which one species splits into two or more species |  | 16 |
| 5318099351 | macroevolution | The development of an entirely new species, which is the broad pattern of evolution over long time spans | 17 | |
| 5318099352 | species | a group of populations whose members have the potential to interbreed in nature and produce viable, fertile offspring- but do not produce viable, fertile offspring with members of other such groups | 18 | |
| 5318099353 | reproductive isolation | the existance of biological barriers that impede members of two species from producing viable offspring | 19 | |
| 5318099354 | hybrids | offspring that result from interspecific mating |  | 20 |
| 5318099355 | prezygotic barriers | impede mating or hinder fertilization if mating occurs (five types: habitat, temporal, behavioral, mechanical, gametic) |  | 21 |
| 5318099356 | post zygotic barriers | prevents hybrid zygote from developing into a viable fertile adult through reducing hybrid viability, reducing hybrid fertility, or hybrid breakdown | 22 | |
| 5318099357 | allopatric speciation | gene flow is interrupted when a population is divided into geographically isolated subpopulations |  | 23 |
| 5318099358 | sympatric speciation | speciation occurs in populations that live in the same geographic area (usually occurs due to polyploidy, habitat differentiation, and sexual selection) |  | 24 |
| 5318099359 | polyploidy | extra sets of chromosomes due to accidents during cell division |  | 25 |
| 5318099360 | autopolyploid | an individual that has more than two chromosome sets that are all derived from a single species |  | 26 |
| 5318099361 | allopolyploid | an individual that has more than two chromosome sets due to two different species interbreeding and after several generations can change a sterile hybrid into a fertile polyploid. Allopolyploids are fertile when mating with each other but cannot interbreed with either parent species |  | 27 |
| 5318099362 | punctuated equilibrium | the theory that in the evolution there are long periods of little morphological change punctuated by relatively short periods of significant change |  | 28 |
| 5318099363 | ribozyme | RNA that can also carry out a number of enzyme-like catalytic functions | 29 | |
| 5318099364 | endosymbiosis | mitochondria and chloroplasts were formally small prokaryotes that began living within larger cells |  | 30 |
| 5318099365 | adaptive radiation | Period of evolutionary change in which groups of organisms form many new species whose adaptations allow them to fill vacant ecological roles in their communities |  | 31 |
| 5318099366 | phylogeny | the evolutionary history of a species or group of species |  | 32 |
| 5318099367 | phylogenetic tree | evolutionary history of a group of organisms represented in a branching diagram |  | 33 |
| 5318099368 | analogous | similarity due to convergent evolution |  | 34 |
| 5318099369 | homologous | similarity due to shared ancestry |  | 35 |
| 5318099370 | clade | a group of species which includes an ancestral species and all of its descendants | 36 | |
| 5318099371 | outgroup | a species or group of species from an evolutionary lineage that is known to have diverged before the lineage that includes the species we are studying | 37 | |
| 5318099372 | maximum parsimony | a principle that states that when considering multiple explanations for an observation, one should first investigate the simplest explanation that is consistent with the facts |  | 38 |
| 5318099373 | molecular clock | a yardstick 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 | 39 | |
| 5318099374 | horizontal gene transfer | a process in which genes are transferred from one genome to another through mechanisms such as exchange of transposable elements and plasmids, viral infection and perhaps fusion of organisms |  | 40 |
| 5318099375 | Darwin's Theory (five parts) | 1. Variation 2. Overproduction 3. Competition 4. Survival of the fittest 5. Emergence of new species (new alleles) | 41 | |
| 5318099376 | Microevolution | Refers to the changes in one gene pool of a population | 42 | |
| 5318099377 | Hardy-Weinberg Equation(s) | the frequencies of alleles and genotypes in a population will remain constant from generation to generation, provided that only Mendelian segregation and recombination of alleles are at work |  | 43 |
| 5318099378 | Mutations | Changes in genetic material and are the raw material for evolutionary change. A single point mutation can introduce a new allele into a population. INCREASE diversity. | 44 | |
| 5318099379 | Nonrandom mating | Individuals choose their mates for a specific reason. The selection of a mate serves to eliminate the less- fit individuals. | 45 | |
| 5318099380 | Genetic Drift | The change in the gene pool due to chance. It is a fluctuation in frequency of alleles from one generation to another and is unpredictable. It tends to LIMIT diversity. (Ex. Bottleneck and Founder effects) | 46 | |
| 5318099381 | Heterozygous | A diploid organism is heterozygous at a gene locus when its cells contain two different alleles of a gene. (Ex. Pp) | 47 | |
| 5318099382 | Homozygous | Homozygous is a genetic condition where an individual inherits the same alleles for a particular gene from both parents. (Ex. PP and pp) Dominant and Recessive | 48 | |
| 5318099383 | Allelic Frequencies | the proportion of a particular allele (variant of a gene) among all allele copies being considered. It can be formally defined as the percentage of all alleles at a given locus on a chromosome in a population gene pool represented by a particular allele. (Ex. p+q=1 where p represents the frequency of the dominant allele while q represents the frequency of the recessive allele) | 49 | |
| 5318099384 | Population | a group of individuals of the same species that live in the same area and interbreed, producing fertile offspring | 50 | |
| 5318099385 | Genotype | An individual's collection of genes. | 51 | |
| 5318099386 | Phenotype | The organism's physical appearance. | 52 | |
| 5318099387 | Genetic Variation | refers to diversity in gene frequencies. Genetic variation can refer to differences between individuals or to differences between populations. | 53 | |
| 5318099388 | Aristotle | Aristotle spoke for the ancient world with his theory of Scala Natura. According to this theory, all life-forms can be arranged on a ladder of increasing complexity, each with its own issued support. The species are permanent and do not evolve. Humans are at the pinnacle of this ladder of increasing complexity. | 54 | |
| 5318099389 | Linnaeus | Linnaeus specialized in taxonomy, the branch of biology concerned with naming and classifying the diverse forms of life. He believed that scientists should study life and that a classification system would reveal a divine plan. He is also known for inventing binomial nomenclature, where an animal has a special scientific name consisting of two parts; a genus and a species. (Ex. the scientific name for lions is Panthera Leo) | 55 | |
| 5318099390 | Cuvier | He studied FOSSILS and realized that each layer of earth is characterized by different fossils. He believed that a series of catastrophes was responsible for the changes in the organisms on earth and was a strong opponent of evolution. His study of fossils was VERY important to Darwin's theory. | 56 | |
| 5318099391 | James Hutton | One of the MOST influential geologists of his day, published his theory of GRADUALISM in 1795. He stated that the Earth had been molded, not by sudden violent events, but by slow, gradual change. He observed the effects of wind, water, and weather and that these were the same forces that formed the various geologic features on earth, such as mountain ranges and canyons. His theories were IMPORTANT because they were based on the idea that the Earth had a verryyyyy long history and that change is the normal course of events. | 57 | |
| 5318099392 | Lyell | Was a leading geologist of Darwin's ERA. He stated that geological change results from slow, continuous actions. He believed that the Earth was much older than the 6,000 years thought by early theologians. His text, "Principles of Geology" was a great influence on Darwin. | 58 | |
| 5318099393 | Lamarck | Was a contemporary of Darwin who also developed a theory of evolution. He published his theory in 1809, the year Darwin was born. His theory relies on the ideas of Inheritance of acquired characteristics and use of disguise. He stated that individual organisms change in response to the environment. | 59 | |
| 5318099394 | Wallace | A naturalist and author, published an essay discussing the process of natural selection identical to Darwin's, which...had not yet been published. | 60 | |
| 5318099395 | Darwin | a naturalist and author, who went to the Galapagos islands to study organisms. By the early 1840's, he had worked out his theory of natural selection but did NOT publish them. He later published "On the origin of the species" in 1859 when he was convinced. Darwin's theory challenged the traditional view of a young earth (6000 yrs old) inhabited by unchanging species. | 61 | |
| 5318099396 | Artificial Selection | Humans breed plants and animals by seeking individual with desired traits as breeding stock. (Ex. racehorses are bred for speed, and laying hens are bred to produce more and larger eggs) | 62 | |
| 5318099397 | Descent with modification | Descent with modification refers to the passing on of traits from parent organisms to their offspring. This passing on of traits is known as heredity, and the basic unit of heredity is the gene. Genes hold information about every conceivable aspect of an organism: its growth, development, behavior, appearance, physiology, reproduction. Genes are the blueprints for an organism and these blueprints are passed from parents to their offspring each generation. | 63 | |
| 5318099398 | Differential Reproductive Success | One individual or group having better success than another. | 64 | |
| 5318099399 | Fitness | is a central idea in evolutionary and sexual selection theories. It can be defined either with respect to a genotype or to a phenotype in a given environment. In either case, it describes individual reproductive success and is equal to the average contribution to the gene pool of the next generation that is made by an average individual of the specified genotype or phenotype. | 65 | |
| 5318099400 | Populations tend to.. | grow exponentially, overpopulate, and exceed their resources. | 66 | |
| 5318099401 | Overpopulation results in... | competition and a struggle for existence | 67 | |
| 5318099402 | In ANY population there is.... | variation and an unequal ability of individuals to survive and reproduce. | 68 | |
| 5318099403 | Only the best-fit individuals.... | survive and get to pass on their traits to offspring. | 69 | |
| 5318099404 | Antibiotic resistance | Directional selection can produce rapid shifts in allelic frequencies. For example, soon after the discovery of antibiotics, bacteria appeared that were resistant to these drugs. Scientists now know that the genes for anti-biotic resistance carried on plasmids, small DNA molecules, which can be transferred from one bacterial cell to another and which can spread the mutation for antibiotic resistance very rapidly within the bacterial population. | 70 | |
| 5318099405 | Geographic variation | when 2 different phenotypes can be found in different regions. | 71 | |
| 5318099406 | Fossils | The fossil record reveals the existence of species that have become extinct or have evolved into other species. Radiometric dating and half life accurately measure the age of fossils. Prokaryotes were the first organisms to develop on earth, and they are the oldest fossils. | 72 | |
| 5318099407 | Biogeography | According to the theory of plate tectonics, continents and oceans rest on giant plates of the Earth's crust that float on top of the hot mantle. Convection currents in the mantle are responsible for the slow, continuous movement of the plates know as continental drift. | 73 | |
| 5318099408 | Comparative anatomy | The study of different structures contributes to scientists' understanding of the evolution of anatomical structures and of evolutionary relationships. ex. the wing of a bat, human arm, and a whale fin, all have the same internal bone structure, although the function of each varies. these structures are known as homologous structures. | 74 | |
| 5318099409 | Analogous Structures | NOT from a recent common ancestor. like a bat wing and a fly's wing have the same function, but the similarity is superficial and reflects adaptation to a similar environment. | 75 | |
| 5318099410 | Divergent Evolution | Occurs when a population becomes isolated (for ANY reason) from the rest of da species, becomes exposed to new selective pressures, and evolves into a new species. | 76 | |
| 5318099411 | Molecular Evidence | Cellular/Molecular Evidence. All living things are fundamentally alike. At the cellular and molecular level living things are remarkably similar to each other. These fundamental similarities are most easily explained by evolutionary theory: life shares a common ancestor. | 77 |
