26. In a species of tree, seed color is determined by four independently assorti

Question

26. In a species of tree, seed color is determined by four independently assorting genes: A, B, C, and D. The wild-type alleles are: A+,B+,C+,and D+. The mutant alleles are all lof and are A-,B-, C-, and D- The lof alleles are unable to work as well. This pathway is diagrammed as shown below. When both red and blue pigments are present, the seeds are purple. Trees with the genotypes A+A-B+B-C+C-D+D. and A+A-B+B-C+C-D-D- were crossed White precursorYellowOrangeRed Blue (a) What color are the seeds of these two parental genotypes? (b) Determine what color offspring seeds are and in what proportions

Explanation / Answer

A) What colour are the seeds in these two parental genotypes?

Purple X red

B) Determine what color offspring seeds are and in what proportions?

Proportion of red (A+ B+ C+ D-D-) = (3/4)(3/4)(3/4)(1/2) = 27/128

Proportion of white (A-A-) = 1/4 = 32/128

Proportion blue (A+ B+ C-C- D+D-) = (3/4)(3/4)(1/4)(1/2) = 9/128

Related Questions

Navigate

• Browse (All)
• Browse 2
• Subjects

---