What is it called when a population has a range of different alleles?
The fact that genes exist in alternate forms, called alleles, forms the basis for the study of population genetics. The collection of all the genes and the various alternate or allelic forms of those genes within a population is called its gene pool. …
What is it called when two populations become genetically different?
Explanation: Speciation occurs when two or more populations become so genetically distinct that they no longer interbreed with one another. There are multiple ways this can occur. … Sympatric speciation occurs when there is no geographical barrier but populations diverge regardless.
What does the variety of alleles in a population account for?
Genetic variation describes naturally occurring genetic differences among individuals of the same species. This variation permits flexibility and survival of a population in the face of changing environmental circumstances.
What is discrete variation?
Discrete variation is either/or and is often caused by the presence or absence of a small number if genes. For example, our ability to “roll” our tongues is determined by just one gene. We can all either roll our tongue or not – there’s nothing in between. … Height is a good example of continuous variation.
What is it called when a population divides into 2 distinct species while living in the same area?
New species arise through a process called speciation. In speciation, an ancestral species splits into two or more descendant species that are genetically different from one another and can no longer interbreed. Darwin envisioned speciation as a branching event.
What is it called when two species reproduce at different times?
Temporal isolation happens when two or more species reproduce at different times.
What is fixation in evolution?
In population genetics, fixation is the change in a gene pool from a situation where there exists at least two variants of a particular gene (allele) in a given population to a situation where only one of the alleles remains. … Similarly, genetic differences between taxa are said to have been fixed in each species.
What is meant by an allele?
An allele is a variant form of a gene. Some genes have a variety of different forms, which are located at the same position, or genetic locus, on a chromosome. … Genotypes are described as homozygous if there are two identical alleles at a particular locus and as heterozygous if the two alleles differ.
What phenotype means?
The term “phenotype” refers to the observable physical properties of an organism; these include the organism’s appearance, development, and behavior. An organism’s phenotype is determined by its genotype, which is the set of genes the organism carries, as well as by environmental influences upon these genes.