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
Unit 7
AP Biology Unit 7 Vocabulary
| Term | Definition |
|---|---|
| Evolution | Descent with modification; the idea that living species are descendants of ancestral species that were different from present day ones; the change in the genetic composition of a population from generation to generation. |
| Evolutionary Fitness | How well a species is able to survive and reproduce in its environment. |
| Natural Selection | A process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits. |
| Selective Pressure | Any cause that reduces or increases reproductive success in a portion of a population. |
| Adaptive Radiation | Period of evolutionary change in which groups of organisms from many new species whose adaptations allow them to fill different ecological roles in their communities. |
| 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. |
| Divergent Evolution | The accumulation of differences between closely related populations within a species, leading to speciation. |
| Gradualism | The hypothesis that evolution proceeds chiefly by the accumulation of gradual changes. |
| Punctuated Equilibrium | In the fossil record, long periods of apparent stasis, in which a species undergoes little or no morphological change, interrupted by relatively brief periods of sudden change. |
| Reproductive Isolation | The existence of biological factors (barriers) that impede members of two species from producing viable, fertile offspring. |
| Speciation | An evolutionary process in which one species splits into 2 or more species. |
| Ecosystems | All organisms in a given area as well as the abiotic factors with which they interact; one or more communities and the physical environment around them. |
| Extinction | The termination of a kind of organism or of a group of kinds, usually a species. |
| Niche | The match of a species to a specific environmental condition. |
| Species Diversity | The number and relative abundance of species in a biological community. |
| RNA World Hypothesis | Life on Earth began with a simple RNA molecule that could copy itself without help from other molecules. |
| Convergent Evolution | The evolution of similar features in independent evolutionary lineages. |
| Bottleneck Effect | Genetic drift that occurs when the size of a population is reduced by natural disasters or human actions. The surviving population is no longer genetically representative of the original population. |
| Founder Effect | The loss of genetic variation that occurs when a new population is established by a very small number of individuals from a larger population. |
| Genetic Drift | A process in which chance events cause unpredictable fluctuations in allele frequencies from one generation to the next. Effects are more visible in small populations. |
| Mutation | A change in the nucleotide sequence of an organism's DNA or in the DNA or RNA of a virus. |
| Population | A group of individuals of the same species that live in the same area and interbreed, producing fertile offspring. |
| Hardy-Weinberg Equilibrium | The principle that frequencies of alleles and genotypes in a population remain the same generation after generation. |
| Migration | Movement from one part of something to another. |
| Null Hypothesis | The hypothesis that there is no significant difference between specified populations, any observed difference being due to sampling or experimental error. |
| Fossil | A preserved remnant or impression of an organism that lived in the past. |
| Isotope | One of several atomic forms of an element, each with the same number of protons but a different number of neutrons, thus differing in atomic mass. |
| Morphology | The branch of biology that deals with the form of living organisms, and with relationships between their structures. |
| Vestigial Structure | A feature of an organism that is a historical remnant of a structure that served a function in the organism's ancestors. |
| Cladogram | A branching diagram showing the cladistic relationship between a number of species. |
| Lineage | A sequence of species each of which is considered to have evolved from its predecessor. |
| Molecular Clock | A method for estimating the time required for a given amount of evolutionary change, based on the observation that some regions of genomes evolve at constant rates. |
| Out-Group | A species or group of species from an evolutionary lineage that is known to have diverged before the lineage that contains the group of species being studied. It is selected so its members are closely related to the group of species being studied. |
| Phylogenetic Tree | A branching diagram that represents a hypothesis about the evolutionary history of a group of organisms. |
| Phylogeny | The evolutionary history of a group of organisms, such as a tribe or a racial group. |
Created by:
AmericaC
Popular Biology sets