Microevolution
is the change in allele frequencies that occurs over time within a population. This change is due to four different processes: mutation, selection (natural and artificial), gene flow and genetic drift. … Ecological genetics concerns itself with observing microevolution in the wild.
What is the term for evolution within a population?
In population genetics, the term evolution is defined as
a change in the frequency of an allele in a population
. Frequencies range from 0, present in no individuals, to 1, present in all individuals. The gene pool is the sum of all the alleles at all genes in a population.
What is the term used to describe genetic changes in a species population?
Evolution
is a process that results in changes in the genetic material of a population over time. Evolution reflects the adaptations of organisms to their changing environments and can result in altered genes, novel traits, and new species.
Darwinism
: Term commonly used as a synonym for evolution. Descent With Modification: Passing down traits that might change over time.
What is the term used to describe the small genetic changes that occur in a population quizlet?
Mutation
is the ultimate source of genetic variation.
How does population genetics support evolution?
Because a genetic population is described as the
sum of gene
(or allelic) frequencies for all the genes represented by that population, it follows that for evolution of a species to occur the gene frequencies of that population must undergo change.
What does introns stand for?
An intron (for
intragenic region
) is any nucleotide sequence within a gene that is removed by RNA splicing during maturation of the final RNA product. In other words, introns are non-coding regions of an RNA transcript, or the DNA encoding it, that are eliminated by splicing before translation.
What is evolution quizlet?
Evolution. Evolution
is change in the heritable traits of biological populations over successive generations
. Adaptation. An adaptation, also called an adaptive trait, is a trait with a current functional role in the life of an organism that is maintained and evolved by means of natural selection.
How does evolutionary change occur quizlet?
Evolution occurs
when the allele frequencies in a population changes
. … Genetic Drift: Random change in allele frequencies in a population due to chance alone.
What term is used to describe a population that is not undergoing evolutionary change?
When a population is in
Hardy-Weinberg equilibrium
, it is not evolving. Learn how violations of Hardy-Weinberg assumptions lead to evolution.
What are three definitions of evolution?
c(1) : a process of continuous change from a lower, simpler, or worse to a higher, more complex, or better state : growth. (2) : a process of gradual and relatively peaceful social, political, and economic advance. d : something evolved. 3 :
the process of working out or developing
.
Which term refers to genetic variation within a species or gene pool quizlet?
genetic polymorphism
. discontinuous genetic variation that results in different forms or types of individuals among the members of a single species; promotes genetic diversity within a population; common example is different allelic forms that make humans have many blood types.
What is defined as a change in allele frequencies in a population over time?
In population genetics,
evolution
is defined as a change in the frequency of alleles (versions of a gene) in a population over time. … In this article, we’ll examine genetic drift, an evolutionary mechanism that produces random (rather than selection-driven) changes in allele frequencies in a population over time.
What is polymorphic variation?
polymorphism, in biology,
a discontinuous genetic variation resulting in the occurrence of several different forms or types of individuals among the members of a single species
. A discontinuous genetic variation divides the individuals of a population into two or more sharply distinct forms.
What does the term genetic drift mean?
Genetic drift is a mechanism of evolution. It refers
to random fluctuations in the frequencies of alleles from generation to generation due to chance events
. Genetic drift can cause traits to be dominant or disappear from a population. The effects of genetic drift are most pronounced in small populations.
What is genetic evolution?
Gene evolution is
concerned with the changes at gene level
, typically with gain of a new gene, loss of an old one, the change in gene structure, and their consequence on the function and evolution of genomes.
What’s an example of convergent evolution?
Convergent evolution is when different organisms independently evolve similar traits. For example,
sharks and dolphins
look relatively similar despite being entirely unrelated. … Another lineage stayed put in the ocean, undergoing tweaks to become the modern shark.
What is an intron vs exon?
An
intron
is a portion of a gene that does not code for amino acids. … The parts of the gene sequence that are expressed in the protein are called exons, because they are expressed, while the parts of the gene sequence that are not expressed in the protein are called introns, because they come in between the exons.
What defines a population in evolution quizlet?
– Population:
A group of individuals of the same species living in the same place at the same time
. … – Microevolution: A change in the relative frequency of alleles in a gene pool over time.
What does an exon do?
An exon is a
coding region of a gene that contains the information required to encode a protein
. In eukaryotes, genes are made up of coding exons interspersed with non-coding introns. These introns are then removed to make a functioning messenger RNA (mRNA) that can be translated into a protein.
What is a spliceosome do?
Abstract. The spliceosome is a large RNA-protein
complex that catalyses the removal of introns from nuclear pre-mRNA
.
What are three definitions of evolution quizlet?
Evolutionary history of one organism
or a group of organism. Natural Selection. Individual that are better suited to their environment survive & reproduce most successfully. Adaptation. Inherited characteristic that increases an organism’s chance of survival.
What is divergent evolution?
What Is Divergent Evolution? Divergent evolution occurs
when a population of animals or plants is split into two groups by a geographic barrier
(for instance, a body of water or a migration to a new area), causing each group to develop different traits under their respective selective pressures and natural selection.
What is the correct description of evolution?
Evolution is defined as
the process of growth and development or the theory that organisms have grown and developed from past organisms
. An example of evolution is how cell phones have changed over time.
How does evolutionary change occur?
In biology, evolution is the change in the inherited traits of a population from generation to generation. … Evolution occurs when
these heritable differences become more common or rare in a population
, either non-randomly through natural selection or randomly through genetic drift.
Which of these is responsible for evolutionary changes in a species?
Natural selection, genetic drift
, and gene flow are responsible for evolutionary change. Natural selection is the predominant mechanism causing evolution.
What is directional selection?
Directional selection occurs
when individuals with traits on one side of the mean in their population survive better or reproduce more than those on the other
. It has been demonstrated many times in natural populations, using both observational and experimental approaches.
What’s an example of artificial selection?
Dog breeding
is another prime example of artificial selection. … Artificial selection has long been used in agriculture to produce animals and crops with desirable traits. The meats sold today are the result of the selective breeding of chickens, cattle, sheep, and pigs.
How do allele frequencies change in populations?
Allele frequencies in a population may change
due to gene flow, genetic drift, natural selection and mutation
. These are referred to as the four fundamental forces of evolution. Note that only mutation can create new genetic variation. The other three forces simply rearrange this variation within and among populations.
What does it mean for a population to be in Hardy-Weinberg equilibrium?
The Hardy-Weinberg equilibrium is a
principle stating that the genetic variation in a population will remain constant from one generation to the next in the absence of disturbing factors
. … For instance, mutations disrupt the equilibrium of allele frequencies by introducing new alleles into a population.
What term refers to an individual living thing?
An organism
is an individual living thing. It is easy to recognize a living thing, but not so easy to define it. Animals and plants are organisms, obviously. Organisms are a biotic, or living, part of the environment.
When was the term evolution first used?
Modern use in biology, of species, first attested
1832
by Scottish geologist Charles Lyell. Charles Darwin used the word only once, in the closing paragraph of “The Origin of Species” (1859), and preferred descent with modification, in part because evolution already had been used in the 18c.
Which statement best represents the meaning of term evolution?
Evolution is a gradual process that occurs over long periods of time. Variation occurs among individuals in a population. Mutations are the ultimate source of genetic variation. Individuals
that possess the most favorable variations have
the best chance of reproducing.
Which of the following is defined as genetic change in a population over multiple generations?
Evolution
is defined as genetic changes in a population over multiple generations. … Macroevolution describes large-scale evolutionary events, such as as the appearance of new species.
Which term refers to a change in the frequency of genetic variations within a species?
Sometimes, there can be random fluctuations in the numbers of alleles in a population. These changes in relative allele frequency, called
genetic drift
, can either increase or decrease by chance over time.
Which of the following leads genetic variation in gene pools?
Genetic variation can be caused by
mutation
(which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism’s offspring).
Which of the following terms is used to describe a gene that has two or more alleles within a population?
A particular genotype is described as
homozygous
if it features two identical alleles and as heterozygous if the two alleles differ.
What causes polymorphisms?
polymorphism can be maintained by a
balance between variation created by new mutations and natural selection
(see mutational load). genetic variation may be caused by frequency-dependent selection. multiple niche polymorphism exists when different genotypes should have different fitnesses in different niches.
What is oop polymorphism?
Polymorphism is one of the core concepts of object-oriented programming (OOP) and describes situations in which something occurs in several different forms. In computer science, it describes the
concept that you can access objects of different types through the same interface
.
What is structural polymorphism?
Abstract. Structural polymorphism of DNA is a widely accepted property. … This indicates the possibility of an
architectural switching at quasipalindromic region between linear duplex
to a cruciform structure.
