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Population dynamics is the branch of life sciences that studies short-term and long-term changes in the size and age composition of populations, ...
Population genetics is the study of the allele frequency distribution and change under the influence of the four evolutionary forces: natural selection, genetic drift, mutation and gene flow.
Population dynamics is the study of marginal and long-term changes in the numbers, individual weights and age composition of individuals in one or several populations, and biological and environmental processes influencing those changes.
(a) A population in an ecological sense is a group of organisms, of the same species, which roughly occupy the same geographical area at the same time ...
Population: A group of organisms, all of the same species, which occupies a particular area. Also, the total number of individuals of a species within an ecosystem, or of any group of similar individuals.
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Population ecology is the study of populations and their interactions with the environment. A population is a group of individuals of a species in a particular area.
1. people inhabiting a territory, as in American population ...
Part of the work of forensic DNA analysis is the creation of population databases for the STR loci studied.
Population changes can be studied using population graphs:
This is an exponential growth curve. This type of curve occurs when a population grows in size under ideal conditions.
Population genomics is the application of genomic technologies to understand populations of organisms.
Some populations go through repeated and regular periods of boom followed by bust.
A population must be large enough that chance occurrences cannot significantly change allelic frequencies significantly. To better understand this point, consider the random flipping of a fair coin.
A population that is closed to genetic material from the outside.
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z ...
No more population growth, population size is constant.
Natality rate is equal to mortality rate.
The population has reached the carrying capacity of the environment.
Students of population genetics learn from their textbooks that levels of genetic diversity are determined by the rate of mutation (the number of new mutations per nucleotide site and generation) and the number of reproducing individuals in the ...
Populations Transition Between Growth and Stability
Limits on population growth can include food supply, space, and complex interactions with other physical and biological factors (including other species).
Populations of living things evolve
Evolution refers to changes in the genetic composition of a population. Genetic changes may result in changes in the physical or behavioral characteristics of the individuals.
Population: A group of individuals of the same species within a given space and time.
Predaceous: Preying upon other organisms, predatory.
Type of genetic drift that occurs as the result of a population being drastically reduced in numbers by an event having little to do with the usual forces of natural selection.
population density ...
population an interbreeding group of individuals of one species occupying a defined geographic area.
predation a relationship in which one population within a community may capture and feed upon another population.
Population. A local group of organisms belonging to the same species and capable of interbreeding.
PPA. See U.S. Department of Agriculture.
Prion. See Proteinaceous infectious particle.
Population: The number of individuals of a particular species that live within a defined area.
Predator: An animal that hunts and kills other animals for food.
Prey: An animal that is used by other animals for food.
Population a group of the same species of organism in the same area at the same time
(populus = the people)
Porphyria a dominant genetic inability to make porphyrin
(porphyr = purple; -ia = state of‚ condition of‚ disease) ...
The study of variation in genes among a group of individuals.
Positional cloning ...
8. A population of an organism reaches steady state; which would most likely have the biggest impact on population density?
Populations evolve. [evolution: a change in the gene pool] In order to understand evolution, it is necessary to view populations as a collection of individuals, each harboring a different set of traits.
Population genetics is basically genetics of the particular traits, or characters, of man, in the case of human population genetics, that then pass between generations with a particular population.
A group of organisms of the same species relatively isolated from other groups of the same species. See deme.
Population density. Number of individuals per unit area or volume
Porifera. The phylum comprising the sponges.
bol.ch - Das einfach runde Partnerprogramm
Complete Biology ...
Population biology - study of the populations of organisms - most often referred as ecology, or used to point out biology adaptations, biology events sum up ...
population A group of organisms of the same species inhabiting a specific geographical locality.
population crash A sudden population decline caused by predation, waste accumulation, or resource depletion; also called a dieback.
Population a group of organisms, usually a group of sexual organisms that interbreed and share a gene pool, and are normally relatively isolated from other groups of the same species.
A population of cultured cells, of plant or animal origin, that has undergone a change allowing the cells to grow indefinitely, in contrast to a cell strain. Cell lines can result from chemical or viral transformation and are said to be immortal.
In population genetics the evolution of a population of organisms is sometimes depicted as if travelling on a fitness landscape. The arrows indicate the preferred flow of a population on the landscape, and the points A, B, and C are local optima.
When a population of bacteria is subjected to an antibiotic, many bacteria are killed, but a few may have the ability to evade death. If so, this ability can be passed to later generations.
Effective population size (N or Ne): number of individuals contributing 'unique' chromosomes to the next generation (Nf = number of mothers in a population; ...
A population of genetically identical cells (or organisms).
View Dr Chromo's lecture on Cloning hosts and vectors
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A population of cells derived from a single cell and thus expected to be genetically identical. Genetic differences in a "clonal" population may arise from random spontaneous mutations during growth of the cells.
mixed cell populations- expression signals: Expression
molecular motors: Nanoscience & Miniaturization ...
The group of related organisms used in constructing a genetic map. (ORNL)
See: genetic marker (ORNL)
Also known as Filtering.
Other ecologists are more interested in how organisms of the same species interact with each other in populations. Still others spend their days examining how whole populations interact with other populations in a community.
The total dry weight of all organisms in a particular sample, population, or area. Bioremediation. The use of microorganisms to remedy environmental problems. See Bioaugmentation, Bioenrichment. Biotechnology.
Genetic variation -- a phenotypic variance of a trait in a population attributed to genetic heterogeneity.
Gene flowChanges in gene frequencies that occur over long periods of time due to migration in which different populations interbreed. An example is the transfer of genes between racial groups, e.g.
Allele frequency — The proportion of chromosomes in a population harboring a specific genetic variant. "Minor allele frequency" typically refers to the less common variant at a biallelic single nucleotide polymorphism.
Community: A group of populations of different species occupying a given place at a given time that are viewed as interdependent. An aggregation of interacting species.
It comes about when sub populations of a species are separated geographically (geographical isolation) or are prevented from engaging in sexual reproduction (sexual isolation) and upon later reunion, they can no longer interbreed.
Differential displayA form of RT-PCR in which primers are used to select a subset of the total mRNA population. This allows comparison of mRNAs from different cells.
This term is defined differently by formal geneticists and population biologists. The formal genetic definition is an allele that exerts a deleterious effect on phenotype.
Though widespread familiarity with the flu makes it seem relatively benign to much of the general population, the virus can be devastating.
Ecology: abiotic, biodiversity, ecological succession, ecology, nitrogen cycle, transpiration, biotic, competition, biome, population model, aggregation, behavior, population density, biological sucession, colonial organism, dispersion, ...
Within a population, the measure of how much of the variation of a particular phenotype is due to environmental factors (as opposed to variations in genotype - see genetic variance).
Polymorphic A term formulated by population geneticists to describe loci at which there are two or more alleles that are each present at a frequency of at least one percent in a population of animals.
This it is a very important task because we are able to know the behavior or functioning of each population when it faces to other individuals from other populations or communities and how the populations or the specific sectors of the biosphere are ...
selection -- Process which favors one feature of organisms in a population over another feature found in the population.
random genetic drift Term used to refer to changes, from one generation to the next, in the population frequency of an allele or trait due to random deviation from the population frequencies expected on the basis of pre-existing frequencies.
Species or populations that occur in geographically separate areas.
A polyploid originating through the addition of unlike chromosome sets, often in conjunction with hybridization between two species.
The measurements of the pelvis given above are fairly accurate, but different figures are given by various authors no doubt due mainly to differences in the physique and stature of the population from whom the measurements have been taken. [back] ...
spontaneous Mutations that occur in the absence of treatment with a chemical or biological mutagen. Usually refers to mutations in natural populations.
See also: Organ, Human, Trans, DNA, Biology