The frequency of a dominant allele r in a population is 0.4. what is the frequency of the recessive allele, r? 0.3

The frequency of the recessive allele (r) is 0.6 , Frequency of dominant allele R  (p) +  freq. of recessive allele r (q) = 1if the frequency of allele R is 0.4 , so freq. of allele r is 0.6

Explanation:

Alleles:

An allele  is a version of a gene, a heritable unit that controls a specific feature of an organism.For example, Mendel studied a gene that controls flower color in pea plants.This gene comes in:  a white allele,w and a purple allele,Ww: recessive allele   but  W: is dominant alleleEach pea plant has two gene copies , which may be the same or different alleles, ex; (WW\ Ww\ ww)  ( see first picture)  If the two gene copies is:

                    WW: this mean pea plant will take purple color

                    Ww: the dominant purple allele,W,  will hide the  recessive                

                             white allele, w,and    pea plant will be purple.

                     ww: pea plant will be white

Allele frequency :

Refers to how frequently a particular allele appears in a population

(A population is a group of organisms of the same species that are found in the same area )

For example : if all the alleles in a population of pea plants were purple alleles, W, the allele frequency of W would be 100%, or 1 However, if half the alleles were W and half were w, each allele would have an allele frequency of 50%, or 0.5

Example: Finding allele frequency: ( see second picture)

Let’s look at an example ( pic. 2)  Consider the very small population of nine pea plants . Each pea plant has two copies of the flower color gene.  If we look at the two gene copies in each plant  ( pic 2 ) and count up how many W copies are present, we find there are 13. If we count up how many w copies are present, we find that there are five. The total number of gene copies in the whole population is 13 + 5 = 18 .We can divide the number of copies of each allele by the total number of copies to get the allele frequency. When there are just two alleles for a gene in a population, their frequencies are given the symbols (p) and (q) :The frequencies of all the alleles of a gene must add up to one             ( p+q=1).

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Allele :

Genes:

Keyword:

Allele\ gene\ frecuency \ mendel \ genetics \heredity