Name: 13. Two different true-breeding pigeon lines both with white feathers were
ID: 197811 • Letter: N
Question
Name: 13. Two different true-breeding pigeon lines both with white feathers were crossed, the F1 offspring were phenotypically identical to the parents (white feathers). The F1 offspring were selfcrossed to produce an F2 with 128 birds with white feathers and 32 birds with colored feathers. Form a hypothesis for this inheritance pattern. A. How many genes are determining feather color in pigeons? B. Define symbols for the gene(s), and write the genotypes and phenotypes of the P1, F1 and F2 generation include ratios. C. Use the Chi-square test, to verify your hypothesisExplanation / Answer
Answer:
True breeding pigeon lines with white feathers were crossed
WWCC x wwcc
Gametes, WC, wc
F1 - All white feathers (WwCc)
F1 were self crossed (WwCc x WwCc)
F2 Generation:
White feathers - 128 birds
Colored feathers - 32 birds
Inheritance pattern: In this case, 2 genes control the color of the feathers. The colored phenotype is the result of dominant epistasis. The white pigeon contains a gene W, which in the dominant state inhibits or suppresses the expression of the dominant colour gene C, resulting in white feathers.
The recessive alleles of the inhibitor gene (ww) produce coloured birds due to expression of gene C. In other words gene W is epistatic to gene C. Dominant epistasis, which produces a segregation ratio such as 12:3:1 or 13:3
Degree of freedom = 1
Probability corresponding to chi square value of 0.1641 for 1 degree of freedom is P-Value = 0.6854. The result is not significant at p < 0.05. Therefore, Null Hypothesis is not rejected.
Observed Expected (O-E) (O-E)^2/E 128 130 -2 0.0308 32 30 2 0.1333 Chi Square (sum) 0.1641Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.