Epistasis

Question 1

What is epistatis?

Answer 1

An interaction between genes when the expression of one gene covers up
covers the expression of another gene
this can happen when a characteristic is controlled by more than one gene

Question 2

What is an example of episttis?

Answer 2

e. g. B = blue pigment b = no pigment

e. g. E - enzyme (Blue to red pigment) e = no enzyme

Question 3

What is the gene 1 epistatic to?

Answer 3

gene 2

Question 4

What happens if the genotype is bb (homozygous recessive?

Answer 4

there will be no pigment

it doesnt matter which alleles for gene 2 are present - there will be no pigment

Question 5

What happens if the gene 1 is Bb or BB?

Answer 5

then gene 2 will be red if the enzyme is Ee EE

it wont turn red and stay blue if the enzyme is ee

Question 6

What does a dihybrid cross on epistatic genes result not result in?

Answer 6

a normal phenotypic ratio

recessive epistatic alle will be 9:3:4

dominant epistatic allele - 12:3:1