Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Biol172_Exam2
| Question | Answer |
|---|---|
| Evolution (Descent with modification) | The idea that living species are descendents of ancestral specials that were different from the present day ones; also defined narrowly as the change in the genetic composition of a population from generation to generation. |
| Gradualism | The principle that change is slow, steady, and gradual of time (uniformity of rate). |
| Uniformitarianism | The principle that mechanisms of change are constant over time. |
| Catastrophism | The principle that events in the past occurred suddenly and were caused by different mechanisms than those operating today. |
| Artificial selection | The selective breeding of domesticated plants and animals to encourage the occurrence of desirable traits. |
| Natural selection | A process in which individuals that have certain inherited traits tend to survice and reproduce at higher rates than other individuals because of those traits. |
| Homologous structure | Structures in different species that are similar because of common ancestry. |
| Vestigial/Rudimentary Structure | A feature of an organism that is a historical remnant of a structure that served a function in the organism’s ancestors. |
| What is the Hardy Weinberg equilibrium equation? | p² + 2pq + q² = 1; where p=frequency of dominant allele and q=frequency of recessive allele. |
| Hardy Weinberg Assumptions | Large population size (less than 1000 can disrupt equilibrium; Isolation from other populations; No net mutations; Random mating; No natural selection |
| Genetic Drift | A process in which chance events cause unpredictable fluctuations in allele frequencies from one generation to the next. Effects are most pronounced in small populations. |
| Bottleneck Effect | Genetic drift that occurs when the size of a population is reduced, as by a natural disaster or human actions. Typically, the surviving population is no longer genetically representative of the original population. |
| Founder Effect | Genetic drift that occurs when few individuals become isolated from a larger population and form a new population whose gene pool composition is not reflective of that of that original population. |
| Introgression | The entry or introduction of a gene from one gene complex into another (as by hybridization). |
| Polymorphism | The occurrence of different forms, stages, or types of individual organisms or organisms of the same species, independent of sexual variations. |
| Balanced Polymorphism | A system of genes in which two alleles are maintained in stable equilibrium because the heterozygote is more fit than either of the homozygotes. |
| Cline | A graded change in a character along a geographical axis. |
| Evolutionary Fitness | The probability that the line of descent from an individual with a specific trait will not die out. |
| Directional Selection | Natural selection in which individuals at one end of the phenotypic range survive or reproduce more successfully than do other individuals. |
| Disruptive Selection | Natural selection in which individuals on both extremes of a phenotypic range survive or reproduce more successfully than do individuals with intermediate phenotypes. |
| Stabilizing Selection | Natural selection in which intermediate phenotypes survive or reproduce more successfully than do extreme phenotypes. |
| Plate Tectonics | The theory that the continents are part of great plates of Earth’s crust that float on the hot underlying portion of the mantle. |
| Continental Drift | Movements in the mantle cause the continents to move slowly over time. |
| Microevolution | Evolutionary change below the species level; change in the allele frequencies in a population over generations. |
| Macroevolution | Evolutionary change above the species level. Examples include the origin of a new group of organism through a series of speciation events and the impact of mass extinctions on the diversity of life and its subsequent recovery. |
| Cladogenesis | Evolutionary change by the branching of new species from common ancestral types. |
| Angenesis | Evolutionary change in a single lineage through time. |
| Biological Species Concept | Definition of a species as 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. |
| Morphological Species Concept | A definition of a species in terms of measurable anatomical criteria. |
| Reproductive Isolation | The existence of biological factors (barriers) that impede members of two species from producing viable, fertile offspring. |
| Prezygotic Barrier | A reproductive barrier that impedes mating between species or hinders fertilization if interspecific mating is attempted. |
| Postzygotic Barriers | A reproductive barrier that prevents hybrid zygotes produced by two different species from developing into viable, fertile adults. |
| Allopatric Speciation | The formation of new species in populations that are geographically isolated from one another. |
| Sympatric Speciation | The formation of a new species in populations that live in the same geographic area. |
| Polyploidy (sympatric speciation) | A chromosomal alterations in which an organism possesses more than two complete chromosome sets. It is the result of accident cell division |
| Adaptive Radiation | Period of evolutionary change in which groups of organisms form many new species whose adaptations allow them to fill different ecological roles in their communities. |
| Punctuated Equilibrium | In the fossil record, long period of apparent stasis, in which a species undergoes little or no morphological change, interrupted by brief periods of sudden change. |
| Paedomorphosis/Neotany | The retention in an adult organism of the juvenile features of its evolutionary ancestors (paedomorphosis – permanent; neotany – reversible) |
| Homeotic Gene Mutation | Mutation of master control genes may influence hundreds of structural genes, so its possible for the emergence of evolutionary novelties to arise much faster than normal. Can cause whole scale change in body plant during development (e.g. extra wings, leg |
| Phylogeny | The evolutionary history of a species or group of related species. |
| Phylogenetic tree | A branching diagram that represents a hypothesis about the evolutionary history of a group of organisms. |
| Systematics | A scientific discipline focused on classifying organisms and determining their evolutionary relationships. |
| Taxonomy | A scientific discipline concerned with naming and classifying the diverse forms of life. |
| Binomial Nomenclature | The two part, Latinized format for naming a species, consisting of genus and specific epithet. |
| Hierarchy of Classification (The Linnaean system) | Grouping of species into a hierarchy of increasingly inclusive categories. The first grouping is built into the binomial: species that appear to be closely related are grouped into the same genus. |
| Beyond genera, taxonomists employ progressively more comprehensive categories of a classification: | Domain: Archaea, Bacteria, and Eukarya; Kingdom; Phylum; Class; Order; Family; Genus; Species |
| Clade | A group of species that includes ancestral species and all of its descendents. |
| Cladogram | Evolutionary tree |
| Monophyletic | Pertaining to a group of taxa that consists of a common ancestor and all of its descendents. Equivalent to a clade. |
| Paraphyletic | Pertaining to a group of taxa that consists of a common ancestor and some, but not all, of its descendents. |
| Polyphyletic | Pertaining to a group of taxa derived from two or more different ancestors. |
| Parsimony | A principle that states that when concerning multiple explanations for an observation, one should first investigate the simplest explanation that is consistent with the facts. |
| Protobiont | Initial structures during the origin of life which can show at least one property of life (e.g. reproduction, metabolism, and maintenance of internal chemical environment). |
| Coacervate | Growing in clusters. |
| Ribozymes | An RNA molecule that functions as an enzyme, such as a intron that catalyzes its own removal during RNA splicing. |
| Radiometric dating | A method for determining the absolute age of rocks and fossils, based on the half-life of radioactive isotopes. |
| Mass Extinction | The elimination of a large number of species throughout the Earth, the result of global environmental changes. |
| Stromatolite | Layered rock that results from activities of prokaryotes that bind thin films of sediment together. |
| Endosymbiosis | A process in which a unicellular organism engulfs another cell, which lives within the host cell and ultimately becomes an organelle of the host cell. |
Created by:
emilyjustine0739
Popular Biology sets