How does epistasis affect proportion of phenotypical form, Biology

Assignment Help:

In the hybridization of 2 genes (4 different alleles, 2 of each pair) how does epistasis affect the proportion of phenotypical forms in the F2 generation?

In the dihybridism without epistasis double heterozygous parental individuals cross and in F2 4 phenotypical forms appear. The amount is 9 double dominant to 3 dominant for the first pair, recessive for the second to 3 recessive for the first pair, dominant for the second to 1 double recessive (9:3:3:1).

Considering so as to the epistatic gene is the second pair and that the recessive genotype of the hypostatic gene means lacking of the characteristic, in the F2 generation of the dominant epistasis the following phenotypical forms would emerge: 13 dominant for the second pair or recessive for the first that is the characteristic does not manifest, 3 dominant for the first pair, recessive for the second That is the characteristic manifests. Phenotypical proportion would be 13:3. In recessive epistasis in F2 the phenotypical forms that would emerge are: 9 double dominant (the characteristic manifests), 7 recessive for the first pair or recessive for the second that is the characteristic does not manifest. hence the phenotypical proportion would be 9:7.

These instances show how epistasis changes phenotypical forms and proportions, from the normal 9:3:3:1 in F2 to 13:3 in the dominant epistasis or to 9:7 in recessive epistasis (note that some forms have even disappeared) and if the recessive genotype of the hypostatic gene is active, not simply meaning that the dominant allele does not manifest, the number of phenotypical forms in F2 changes.

 


Related Discussions:- How does epistasis affect proportion of phenotypical form

Why do male and female gametes diffrent from each other, Q. Concerning thei...

Q. Concerning their size and basic morphology how and why do the male and the female gametes differentiate from each other? The female gametes are big cells full of vitellus (n

Why is knowledge of chemistry necessary for study, Why is knowledge of chem...

Why is knowledge of chemistry necessary for the study of living organisms?

Sea Lampreys, #questiHow do the non parasitic lampreys interact with other ...

#questiHow do the non parasitic lampreys interact with other members of their ecosystem in comparison to their parasitic cousinson..

Membrane oxygenators-type of oxygenators , Membrane Oxygenators: They are...

Membrane Oxygenators: They are more physiological and are similar to natural lungs. There is separation of blood and gas by membrane across which gas exchange takes place. There

Odyssey, how does odysseus get the dead to talk to him?

how does odysseus get the dead to talk to him?

Why haploid cell attempted to perform meiosis, What problem would most like...

What problem would most likely to occur if a haploid cell attempted to perform meiosis? a.The cell could not replicate its DNA prior to meiosis. b.The cell could not pair hom

Contraceptive pill - reproduction, Contraceptive Pill - Reproduction ...

Contraceptive Pill - Reproduction About sixty million women in the world are currently using oral steroid contraceptives. These contraceptives usually consist of a synthetic

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd