In peas yellow is dominant and green is recessive. You have crossed green peas t
ID: 202584 • Letter: I
Question
In peas yellow is dominant and green is recessive. You have crossed green peas to yellow peas and obtained all yellow peas.
Indicate the genotype of each parent and the genotype of the F1 progeny.
You self-cross the F1 and get 115 individuals 32 green. Give the expected outcome for this cross and perform Chi Squared analysis to determine if this is likely a Mendelian trait (be sure to give expected and observed, show your calculations, and indicate your degrees of freedom).
You select an individual from the F2 progeny at random and self-cross it. Using your expected values determine what the probability of getting all yellow. What is the probability of getting a mixture of yellow and green (please show your work)/
Explanation / Answer
ANSWER:
GENOTYPE OF EACH PARENT is one, with phenotype being all yellow peas(YY) not green peas (GG)
F1 progeny genotype is all DOMINANT alleles (YyGg).
F2 progeny will have progeny in ratio 9:3:3:1.
observed green peas (gg) = 32
expected = 1/4 * 115= 28.75
degree of freedom = 2-1 = 1
d= observed- expected= 32- 28.75 =
3.25
2 = (observed-expected)2 / (expected).
= (3.25)2 / (28.75)
= 0.367
as the 2 value is greater than 5 in 100 (P > 0.05),
our hypothesis is accepted.
probability of getting all yellow is 3/4
getting a mixture is 1/4 * 1/4.