AP Biology Evolution Flashcards

6458821897	homologous structures	structures in different species that are similar because of common ancestry	0
6458821898	vestigial structures	remnants of features that served important functions in the the organism's ancestors	1
6458821899	convergent evolution	the independent evolution of similar features in different lineages	2
6458821900	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	3
6458821901	gene pool	the aggregate of all of the alleles for all of the loci in individuals in a population	4
6458821902	population	a group of individuals of the same species that live in the same area and interbreed, producing fertile offspring	5
6458821903	natural selection	a process in which organisms with certain inherited characteristics are more likely to survive and reproduce than are organisms with other characteristics	6
6458821904	genetic drift	changes in the gene pool due to random events	7
6458821905	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	8
6458821906	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	9
6458821907	gene flow	the transfer of alleles into or out of a population due to the movement of fertile individuals or their gametes	10
6458821908	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	11
6458821909	disruptive selection	when conditions favor individuals at both extremes of a phenotypic range over individuals with intermediate phenotypes	12
6458821910	stabilizing selection	acts against both extreme phenotypes and favors intermediate variants	13
6458821911	sexual selection	a form of natural selection in which individuals with certain inherited characteristics are more likely than other individuals to obtain mates	14
6458821912	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)	15
6458821913	diploidy	the state of being diploid, that is having two sets of chromosomes	16
6458821914	heterozygote advantage	when individuals who are heterozygous at a particular locus have greater fitness than do both kind of homozygous	17
6458821915	frequency-dependent selection	fitness of a phenotype declines if it becomes too common in the population	18
6458821916	speciation	the process by which one species splits into two or more species	19
6458821917	microevolution	changes over time in allele frequencies in a population	20
6458821918	macroevolution	the broad pattern of evolution over long time spans	21
6458821919	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	22
6458821920	reproductive isolation	the existance of biological barriers that impede members of two species from producing viable offspring	23
6458821921	hybrids	offspring that result from interspecific mating	24
6458821922	prezygotic barriers	impede mating or hinder fertilization if mating occurs (five types: habitat, temporal, behavioral, mechanical, gametic)	25
6458821923	post zygotic barriers	prevents hybrid zygote from developing into a viable fertile adult through reducing hybrid viability, reducing hybrid fertility, or hybrid breakdown	26
6458821924	allopatric speciation	gene flow is interrupted when a population is divided into geographically isolated subpopulations	27
6458821925	sympatric speciation	speciation occurs in populations that live in the same geographic area (usually occurs due to polyploidy, habitat differentiation, and sexual selection)	28
6458821929	punctuated equilibrium	the theory that in the evolution there are long periods of little morphological change punctuated by relatively short periods of significant change	29
6458821930	ribozyme	RNA that can also carry out a number of enzyme-like catalytic functions	30
6458821931	protobionts	collections of abiotically produced molecules surrounded by a membrane-like structure with simple chemical reactions (precursor of prokaryotic cells)	31
6458821932	endosymbiosis	mitochondria and chloroplasts were formally small prokaryotes that began living within larger cells	32
6458821933	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	33
6458821934	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	34
6458821935	phylogeny	the evolutionary history of a species or group of species	35
6458821936	systematics	study and classification of biodiversity and determining their evolutionary relationships	36
6458821937	phylogenetic tree	evolutionary history of a group of organisms represented in a branching diagram	37
6458821938	analogy	similarity due to convergent evolution	38
6458821939	homology	similarity due to shared ancestry	39
6458821940	clade	a group of species which includes an ancestral species and all of its descendants	40
6458821941	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	41
6458821944	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	42
6458821945	Darwin's Theory (five parts)	1. Variation 2. Overproduction 3. Competition 4. Survival of the fittest 5. Overtime, emergence of new species (new alleles)	43