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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 distribution of and change in allele frequencies under the influence of the four evolutionary forces: natural selection, genetic drift, mutation and migration.
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.
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.
More Biology Terms ...
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's gene pool is defined by its allele frequencies.
A population is a localized group of individuals that belong to the same species.
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.
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 ...
The sum of the fitnesses of the genotypes of a population weighted by their proportions; hence a weighted mean fitness.
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 dynamics The study of the factors that affect the growth, stability, and decline of populations, as well as the interactions of those factors.
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.
Populations or species with low genetic diversity at many genes are at risk. When diversity is very low, all the individuals are nearly identical.
A group of organisms of the same species relatively isolated from other groups of the same species. See deme.
Population of transgenic salmon have been produced in which individuals grow rapidly
These transgenic fish could compete for food with other fish species
Cells & Molecules
Cell Division ...
Population density. Number of individuals per unit area or volume
Porifera. The phylum comprising the sponges.
Populations of cells in apical meristem which reproduce much more slowly than other meristematic cells
Resistant to radiation and chemical damage
Possibly a reserve which can be called into action if the apical meristem becomes damaged ...
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.
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
Related Links ...
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.
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.
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.
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 ...
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.
Genetic Distance: various statistics for measuring the 'genetic distance' between subgroups or populations.
- The movement of genes from one population to another by way of interbreeding of individuals in the two populations
- Determining the relative locations of genes on a chromosome.
control action threshold. Pest population level at which treatment is necessary to prevent economic loss, also called economic threshold.
cornicle. Two tubular structures located on the posterior part of an aphid's abdomen.
Gene flow: The exchange of genetic traits between populations by movement of individuals, gametes, or spores. It involves the spread of new variants among different populations through dispersal.
Those organisms are removed from the population so that healthier animals can survive. But the virus life cycle, that of a parasite, only hurts the organisms. Some even destroy cells in order to reproduce.
The natural processes involved are
genetic variation among members of a population
inheritance of those variations by offspring
natural selection, the survival and enhanced reproduction of organisms with favorable variations.
Warts are caused by the human papillomavirus. About half the population of children have them at some time. Warts appear about 1-8 months after infection and can last for years if not treated.
Single base differences of DNA sequences between individuals of a population. For PCR screening and detection of SNP, please visit Primo SNP. See also PCR Glossary.
PubMed Google ...
Penetrance: The percentage of individuals in a population that actually exhibit the (mutant) phenotype even though they carry the mutation ...
3. What would eventually happen to the population of the beans that "survived" the worst? Why?
the legal prohibition of movement of animals from a population with disease ...
polymorphic; polymorphous (relating to the occurrence of more than one kind of individual (independent of sexual differences) in an interbreeding population)
isomorphic; isomorphous (having similar appearance but genetically different) ...
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, Biology, Species