Monday, February 13, 2012

Phenotypic ration from crossing heterozygous females with yellow-green males based on the info. below?

A flowering plant has sex determining mechanism such that XY=male, XX= female. Winge has described a recessive allele on the X-chromosome that lethal when homozygous in female plants, but produces a yellow green uneven color when present in the single X-chromosome ot he the male plant. Normal males and females and heterozgous females are dark green.

Phenotypic ration from crossing heterozygous females with yellow-green males based on the info. below?
Let's say:

XX = Normal, dark green female

XY = Normal, dark green male

X'X = Carrier, dark green female

X'Y= Normal, yellow-green male

X'X' = Lethal, female



X'X x X'Y



___X'___X



X'_X'X'__X'X



Y_X'Y___XY



25% Lethal, female

25% Carrier, dark green female

25% Normal, yellow-green male

25% Normal, dark green male


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