Question

1. What is the difference between two genes affecting a single character and epistasis? What is special about epistasis? 2. How can we use the genotypic abbreviations of phenotype (shorthand gentotypes) (e.g., 9A_B_, 3A_bb, 3aaB_, laabb) to understand what is happening in epistasis? 3. For the example of the Y allele in mice (from the text), explain why yellow coat coloration is dominant, but lethality is recessive. You may use figures to support your argument.

Answer 1

1.) Two genes affecting a single characters nyan means a single phenotypes is controlled by two genes rea multiple genes which include epistasis as well as co-dominance where mullible genes (2 genes) Control single characters. While in case of epistasis. there is making the effect of me genes by other genes Epistasis does not required dominant genes to haphen, it can also occured by recessive genes Existasis is present in nature showing the imbarfance in gene interaction. This is a speciality of ebistass a 2) Genotype abbreviation like A_Bm showing bresence of a dominant genes at both allele that contribute ina (9/16) maximum fraction of ebistaste population

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