FlashcardsChapter02
(35 cards)
Term
Description
Adaptations
Changes in physical structure, function, or behavior that allow an organism or species to survive and reproduce in a given environment.
Adaptive radiation
The diversification of an ancestral group of organisms into new forms that are adapted to specific environmental niches.
Allele
One or more alternative forms of a gene.
Blending inheritance
An outdated, disreputed theory that the phenotype of an offspring was a uniform blend of the parent’s phenotypes.
Catastrophism
The doctrine asserting that cataclysmic events (such as volcanoes, earthquakes, and floods), rather than evolutionary processes, are responsible for geologic changes throughout Earth’s history.
Chromosomes
The strand of DNA found in the nucleus of eukaryotes that contains hundreds or thousands of genes.
Demography
The study of population, especially with regard to birth, survival, and death and the major factors that influence these three key parts of life.
Deoxyribonucleic acid (DNA)
A double stranded molecule that provides the genetic code for an organism, consisting of phosphate, deoxyribose sugar, and four types of nitrogen bases.
Dominant
Refers to an allele that is expressed in an organism’s phenotype and that simultaneously masks the effects of another allele, if another one is present.
Endemic
Refers to a characteristic or feature that is natural to a given population or environment.
Evolutionary biology
The study of organisms and their changes.
Evolutionary synthesis
A unified theory of evolution that combines genetics with natural selection.
Fossils
Physical remains of part or all of once-living organisms, mostly bones and teeth, that have become mineralized by the replacement of organic with inorganic materials.
Gemmules
As proposed by Darwin, the units of inheritance, supposedly accumulated in the gametes so they could be passed on to offspring.
Gene
The basic unit of inheritance; a sequence of DNA on a chromosome, coded to produce a specific protein.
Gene flow
Admixture, or the exchange of alleles between two populations.
Genetic drift
The random change in allele frequency from one generation to the next, with greater effect in small populations.
Genotype
The genetic makeup of an organism; the combination of alleles for a given gene.
Genus
A group of related species.
Geology
The study of the Earth, especially with regard to its composition, activity, and history.
Habitat
The specific area of the natural environment in which an organism lives.
Lamarckism
First proposed by Lamarck, the theory of evolution through the inheritance of acquired characteristics in which an organism can pass on features acquired during its lifetime.
Mendelian inheritance
The basic principles associated with the transmission of genetic material, forming the basis of genetics, including the law of segregation and the law of independent assortment.
