Natural selection on polygenic traits can affect the distributions of phenotypes in three ways:
directional selection, stabilizing selection, or disruptive selection
.
What are 3 ways variation of traits occur?
For a given population, there are three sources of variation:
mutation, recombination, and immigration of genes
. However, recombination by itself does not produce variation unless alleles are segregating already at different loci; otherwise there is nothing to recombine.
What are the 3 ways in which natural selection can change a distribution of traits?
Natural selection on polygenic traits can affect the distributions of phenotypes in three ways:
directional selection, stabilizing selection, or disruptive selection
.
What are three ways to add genetic information to increase variations in a population?
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).
How could gene flow affect a population that was founded by a small number of individuals?
A smaller population is
more vulnerable to genetic drift
because it has a smaller gene pool and is therefore more likely to be affected by chance.
What are the three types of natural selection?
- Stabilizing Selection.
- Directional Selection.
- Disruptive Selection.
What can natural selection act on?
Natural selection acts on
an organism’s phenotype, or observable features
. Phenotype is often largely a product of genotype (the alleles, or gene versions, the organism carries).
What are the two main causes of variation?
The two main causes of variation are
mutation and genetic recombination in sexual reproduction
.
What are the two types of variation?
If you consider almost any characteristic, you will find differences between various people (or other animals or plants) in a population. There are two forms of variation:
continuous and discontinuous variation
.
What is variation and its types?
Variations are
the differences in the genetic makeup or phenotype of various organisms
. Variations arise due to mutation, recombination at the time of gamete formation or due to environmental factors. Variations can be categorised into two types: … These are caused due to mutation, recombination, etc.
What are three ways to add genetic information to increase variations in a population quizlet?
- Genetic drift. – allele frequencies change due to chance.
- Gene flow. – the movement of alleles from one population to another changes the allele frequencies of both populations.
- Mutation. – new alleles are formed. …
- Sexual selection. – certain traits increase mating success. …
- Natural selection.
What are some ways in which variations increase in a population?
Gene duplication, mutation, or other processes can produce new genes and alleles
and increase genetic variation. New genetic variation can be created within generations in a population, so a population with rapid reproduction rates will probably have high genetic variation.
What are the two main sources of genetic variation?
Natural selection acts upon two major sources of genetic variation:
mutations and recombination of genes through sexual reproduction
.
What produces gene flow?
Gene flow is the movement of genes into or out of a population. Such movement may be due to
migration of individual organisms that reproduce in their new populations
, or to the movement of gametes (e.g., as a consequence of pollen transfer among plants).
What are the two types of gene flow?
Alternatively, gene flow can take place between two different species through
horizontal gene transfer
(HGT, also known as lateral gene transfer), such as gene transfer from bacteria or viruses to a higher organism, or gene transfer from an endosymbiont to the host.
What are examples of gene flow?
Gene flow is the movement of genes from one population to another population. Examples of this include
a bee carrying pollen from one flower population to another
, or a caribou from one herd mating with members of another herd.
