In spotted cattle, the colored regions may be mahogany or red. If a red female a

Question

In spotted cattle, the colored regions may be mahogany or red. If a red female and a mahogany male, both derived from separate true-breeding lines, are mated and the cross is carried to an F2 genertion, the following results are obtained: F1: 1/2 mahogany males, 1/2 red females F2: 3/8 mahogany males, 1/8 red males, 1/8 mahogany females, 3/8 red females. When the reciprocal cross to the original was done (mahogany female and red male) identical resltsare obtained. Explain these results by postulating how the color is genetically determined, and diagram the crosses showing appropriate genotypes and phenotypes/

Explanation / Answer

The color encoding alleles exhibit co-dominance resulting in 1:1 proportion of offsprinf

MM(mahogany male) X mm (red female)

F1 offspring : Mm and Mm in 1:1 ratio

F2 offspring 3 mahogany males and 3 red males, 1 red and 1 mahogany females. The color detemination depends on sex linked determination. The M genotype dominant in male encoding mahogany color and m (red) is recessive in females. The m is dominant in females and recessive in males.

Related Questions

Navigate

• Browse (All)
• Browse I
• Subjects

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