AP Biology - Evolution Flashcards

13598535166	convergent evolution	the independent evolution of similar features in different lineages	0
13598535167	population	a group of individuals of the same species that live in the same area and interbreed, producing fertile offspring	1
13598535168	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	2
13598535169	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	3
13598535170	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	4
13598535171	disruptive selection	when conditions favor individuals at both extremes of a phenotypic range over individuals with intermediate phenotypes	5
13598535172	stabilizing selection	acts against both extreme phenotypes and favors intermediate variants	6
13598535173	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)	7
13598535174	heterozygote advantage	when individuals who are heterozygous at a particular locus have greater fitness than do both kind of homozygous	8
13598535175	microevolution	changes over time in allele frequencies in a population	9
13598535176	macroevolution	the broad pattern of evolution over long time spans	10
13598535177	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	11
13598535178	reproductive isolation	the existance of biological barriers that impede members of two species from producing viable offspring	12
13598535179	hybrids	offspring that result from interspecific mating	13
13598535180	prezygotic barriers	impede mating or hinder fertilization if mating occurs (five types: habitat, temporal, behavioral, mechanical, gametic)	14
13598535181	post zygotic barriers	prevents hybrid zygote from developing into a viable fertile adult through reducing hybrid viability, reducing hybrid fertility, or hybrid breakdown	15
13598535182	allopatric speciation	Speciation occurs as a result of geographic isolation.	16
13598535183	sympatric speciation	speciation occurs in populations that live in the same geographic area (usually occurs due to polyploidy, habitat differentiation, and sexual selection)	17
13598535184	endosymbiosis	mitochondria and chloroplasts were formally small prokaryotes that began living within larger cells	18
13598535185	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	19
13598535186	phylogeny	the evolutionary history of a species or group of species	20
13598535187	phylogenetic tree	evolutionary history of a group of organisms represented in a branching diagram	21
13598535188	Abiogenesis	origin of life from nonliving matter	22
13598535189	Artificial selection	The selective breeding of domesticated plants and animals to encourage the occurrence of desirable traits	23
13598535190	Endosymbiosis	A process in which a unicellular organism engulfs another cell, which lives within the host cell and ultimately becomes an organelle in the host cell. Example: Mitochondria and chloroplasts were once independent cells.	24
13598535191	Founder effect	Genetic drift that occurs when a few individuals become isolated from a larger population and form a new population whose gene pool composition is not reflective of that of the original population	25
13598535192	Hardy-Weinberg principle	The principle that frequencies of alleles and genotypes in a population remain constant from generation to generation, provided that only Mendelian segregation and recombination of alleles are at work	26
13598535193	Heterozygous advantage	Greater reproductive success of heterozygous individuals compared with homozygotes and tends to preserve variation in a gene pool (example: carriers of the sickle cell allele, which are immune to malaria but are not homozygous and do not have the sickle cell disease).	27
13598535194	Macroevolution	Evolution which results in speciation (formation of a new species).	28
13598535195	Microevolution	Evolutionary change within a population. A change in the allele frequencies in a population over generations.	29
13598535196	Phylogenic tree	A branching diagram that represents a hypothesis about the evolutionary history of a group of organisms	30
13598535197	Sympatric speciation	The formation of new species in populations that live in the same geographic area	31
13598535251	evolutionary adaptation	An accumulation of inherited characteristics that enhance organisms' ability to survive and reproduce in specific environments.	32
13598535252	artificial selection	human modification of species for desired traits through selective breeding	33
13598535253	descent with modification	each living species has descended, with changes, from other species over time	34
13598535254	founder effect	When a small number of individuals colonize a new area; the new gene pool is not reflective of original population.	35
13598535255	fitness	ability of an organism to survive in its environment and pass on its genes	36
13598535256	homology	Similarity resulting from common ancestry.	37
13598535257	population genetics	Study of allele frequency distribution and change under the influence of evolutionary processes.	38
13598535258	Hardy-Weinberg Theorem	measures changes in allele frequencies over time; Provides an "ideal" population to use as a basis of comparison.	39
13598535259	sexual recombination	Crossing over and shuffling of genes during meiosis.	40
13598535260	quantitative characteristic	Characteristic that varies along a continuum, usually due to influence of two or more genes.	41
13598535261	geographic variation	Difference in variation between population subgroups in different areas.	42
13598535262	cline	A graded change in a trait along a geographic axis.	43
13598535263	relative fitness	Fitness of a particular genotype.	44
13598535264	directional selection	Shift in allele frequency toward a favorable variation.	45
13598535265	disruptive selection	Shift in allele frequency toward the extremes of a range of phenotypes	46
13598535266	stabilizing selection	Shift in allele frequency that favors the average trait	47
13598535267	heterozygous advantage	condition where heterozygotes are fittent; maintains recessive alleles in a population; ex: Sickle Cell Anemia	48
13598535268	sexual selection	certain traits increase mating success	49
13598535269	sexual dimorphism	Differences between the sexes in secondary sexual characteristics.	50
13598535270	biological species concept	A species is a group of populations whose members have the potential to produce fertile offspring.	51
13598535271	reproductive isolation	Barriers that impede members of two different species from producing fertile offspring.	52
13598535272	prezygotic barriers	Barriers that impede mating or hinder fertilization.	53
13598535273	habitat isolation	two species do not interbreed because they encounter each other only rarely.	54
13598535274	temporal isolation	two species do not interbreed because they breed at different times of day, season, or years.	55
13598535275	behavioral isolation	two species do not interbreed because they have incompatible courtship rituals, pheromones, or bird songs.	56
13598535276	mechanical isolation	two species do not interbreed because morphological differences prevent fertilization.	57
13598535277	gametic isolation	two species do not interbreed because sperm can't fertilize the eggs.	58
13598535278	postzygotic barriers	Barriers that prevent the hybrid zygote from becoming a fertile adult.	59
13598535279	reduced hybrid viability	genes of different species interact and impair hybrid development.	60
13598535280	reduced hybrid fertility	Sterile hybrids, often due to uneven chromosome number.	61
13598535281	hybrid breakdown	Hybrid is fertile, but when they breed the next generation is sterile.	62
13598535282	allopatric speciation	When a population is divided; leads to speciation.	63
13598535283	sympatric speciation	Speciation without a divided population.	64
13598535284	polyploidy	In plants, the result of an extra set of chromosomes during cell division.	65
13598535285	adaptive radiation	Evolution of many new species from a common ancestor as a result of introduction to new environments.	66
13598535286	systematics	Analytical approach to understanding the diversity and relationships of present and past organisms.	67
13598535287	analogy	Anatomical similarity due to convergent evolution; creates analogous structures	68
13598535288	clade	A taxonomic grouping that includes only a single ancestor and all of its descendants.	69
13598535289	cladistics	A phylogenetic classification system that uses shared derived characters and ancestry as the sole criterion for grouping taxa.	70
13598535290	monophyletic group	A taxonomic grouping that includes an ancestral species and all of its descendants.	71
13598535291	paraphyletic group	A monophyletic group in which some descendants of the common ancestor have been removed.	72
13598535292	polyphyletic group	A taxonomic grouping consisting of several species that lack a common ancestor (more work is needed to uncover species that tie them together into a monophyletic clade).	73
13598535293	shared primitive character	Trait shared beyond the taxon.	74
13598535294	shared derived character	Evolutionary novelty unique to that clade.	75
13598535295	outgroups	Species or group of species closely related to the ingroup.	76
13598535296	Miller-Urey Experiment	Experiment that found that organic molecules can form in a strongly reducing atmosphere.	77
13598535297	radiometric dating	Dating using decay of radioactive isotopes.	78
13598535298	radioisotopes	Isotopes that have unstable nuclei and undergo radioactive decay.	79
13598535299	endosymbiotic theory	Ancestors of mitochondria and plastids were prokaryotes that came to live in a host cell.	80
13598535300	colony	Collection of autonomously replicating cells.	81
13598535301	antibiotic resistance	Resistance evolving rapidly in many species of prokaryotes due to overuse of antibiotics, especially in agriculture.	82
13598535198	homologous structures	structures in different species that are similar because of common ancestry	83
13598535199	vestigial structures	remnants of features that served important functions in the the organism's ancestors	84
13598535200	convergent evolution	the independent evolution of similar features in different lineages	85
13598535201	Hardy-Weinberg	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	86
13598535202	gene pool	the aggregate of all of the alleles for all of the loci in individuals in a population	87
13598535203	population	a group of individuals of the same species that live in the same area and interbreed, producing fertile offspring	88
13598535204	natural selection	a process in which organisms with certain inherited characteristics are more likely to survive and reproduce than are organisms with other characteristics	89
13598535205	genetic drift	changes in the gene pool due to random events	90
13598535206	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	91
13598535207	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	92
13598535208	gene flow	the transfer of alleles into or out of a population due to the movement of fertile individuals or their gametes	93
13598535209	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	94
13598535210	disruptive selection	when conditions favor individuals at both extremes of a phenotypic range over individuals with intermediate phenotypes	95
13598535211	stabilizing selection	acts against both extreme phenotypes and favors intermediate variants	96
13598535212	sexual selection	a form of natural selection in which individuals with certain inherited characteristics are more likely than other individuals to obtain mates	97
13598535213	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)	98
13598535214	diploidy	the state of being diploid, that is having two sets of chromosomes	99
13598535215	heterozygote advantage	when individuals who are heterozygous at a particular locus have greater fitness than do both kind of homozygous	100
13598535216	frequency-dependent selection	fitness of a phenotype declines if it becomes too common in the population	101
13598535217	speciation	the process by which one species splits into two or more species	102
13598535218	microevolution	changes over time in allele frequencies in a population	103
13598535219	hybrids	offspring that result from interspecific mating	104
13598535220	prezygotic barriers	impede mating or hinder fertilization if mating occurs (five types: habitat, temporal, behavioral, mechanical, gametic)	105
13598535221	post zygotic barriers	prevents hybrid zygote from developing into a viable fertile adult through reducing hybrid viability, reducing hybrid fertility, or hybrid breakdown	106
13598535222	allopatric speciation	gene flow is interrupted when a population is divided into geographically isolated subpopulations	107
13598535223	sympatric speciation	speciation occurs in populations that live in the same geographic area (usually occurs due to polyploidy, habitat differentiation, and sexual selection)	108
13598535224	polyploidy	extra sets of chromosomes due to accidents during cell division	109
13598535225	punctuated equilibrium	the theory that in the evolution there are long periods of little morphological change punctuated by relatively short periods of significant change	110
13598535226	endosymbiosis	mitochondria and chloroplasts were formally small prokaryotes that began living within larger cells	111
13598535227	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	112
13598535228	homeotic genes	master regulatory genes that determine such basic features as where a pair of wings and a pair of legs will develop on a bird or how a plant's flower parts are arranged	113
13598535229	phylogeny	the evolutionary history of a species or group of species	114
13598535230	phylogenetic tree	evolutionary history of a group of organisms represented in a branching diagram	115
13598535231	analogy	similarity due to convergent evolution	116
13598535232	homology	similarity due to shared ancestry	117
13598535233	clade	a group of species which includes an ancestral species and all of its descendants	118
13598535234	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	119
13598535235	Darwin's Theory (five parts)	1. Variation 2. Overproduction 3. Competition 4. Survival of the fittest 5. Overtime, emergence of new species (new alleles)	120
13598535236	Abiogenesis	origin of life from nonliving matter	121
13598535237	abiotic synthesis	formation of organic molecules from inorganic material	122
13598535238	extinction	total disappearance of all members of a species	123
13598535239	mass extinction	total disappearance of a large number a species within a few million years	124
13598535240	extant	still in existance	125
13598535241	fitness	ability to produce surviving offspring	126
13598535242	morphological species concept	new species differ by physical characteristics known as diagnostic traits	127
13598535243	evolutionary species concept	members of a species share distinct evolutionary pathway and common traits	128
13598535244	phylogenetic species concept	a family tree is used to identify species based on a common ancestor	129
13598535245	biological species concept	species are identified as separate because of reproductive isolation.	130
13598535246	plate tectonics	branch of geology which follows the movement of pieces of Earth's crust which float on a lower, hot mantle layer	131
13598535247	continental drift	change over time of the positions of the continents	132
13598535248	fossil	remains and traces of evidence of past life	133
13598535249	paleontology	study of the fossil record	134
13598535250	absolute dating	relies on radiometric dating to assign an age to a fossil	135