17. In poultry white may be due to the homozygous condition of genes at two diff

Question

17. In poultry white may be due to the homozygous condition of genes at two different loci. There recessive genes are cc and oo. Color depends upon the presence of at least one dominant gene for each loci. Therefore C and O must be present to have a colored bird. White males of the genotype CCoo are crossed with white females of the formula ccOO. The colored F1 birds are crossed to birds that are homozygous recessive for both results were as follows: 68 colored and 204 white. Diagram what would be expected if these genes segregated by independent assortment.

Explanation / Answer

Parental cross: CCoo X ccOO
Gametes: (Co) X (cO)
F1 progeny: CcOo

F1 progeny is crossed to homozygous white birds.
Cross: CcOo X ccoo
Gametes: (CO) (Co) (cO) (co) X (co)
Progeny: CcOo Ccoo ccOo coco
Phenotypic ratio = 1 (Colored) : 1 (White)

If either C or O is sufficient to cause color production, 3/4th of the progeny would be colored and 1/4th of the progeny would be white.

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.