The reciprocal cross gives a different result. A reciprocal cross between white-eyed females and red-eyed males gives an F1 in which all the females are red eyed, but all the males are white eyed. The F2 consists of one-half red-eyed and one-half white-eyed flies of both sexes.
Would it ever be possible to cross two red eyed fruit flies and get a white eyed fly?
Surprisingly, this cross yielded a 1:1:1:1 ratio of red-eyed females to white-eyed females to red-eyed males to white-eyed males. … All possible combinations of white eyes and sex are possible. The white-eye trait can be carried over to females when F1 females are crossed with white-eyed males.
What happens when you cross a white eyed female fruit fly with a red eyed male fruit fly?
A white-eyed female fruit fly is crossed with a red-eyed male. Red eyes are dominant, and X-linked. What are the expected phenotypes of the offspring? All of the females will have red eyes; half of the males will have red eyes, and half of the males will have white eyes.
Can male fruit flies have white eyes?
The eye color gene is located on the X chromosome (one of the sex determining chromosomes of Drosophila). White eye color is recessive. When a red eyed male mates with white eyed females, their daughters will have red eyes, but their sons will have white eyes.
What was the gender of all of the white-eyed flies?
Although the first generation of 1,237 offspring was all red-eyed but for three, white-eyed flies appeared in larger numbers in the second generation. Surprisingly, all white-eyed flies were male.
What does a female fruit fly need for white eyes?
1. In fruit flies, the gene for white eyes is sex-linked recessive. (R) is red and (r) is white. Cross a white- eyed female with a normal red-eyed male.
What would be the result of a cross between a white eyed female and a red eyed male?
The genotypes are shown in Figure 2-15 . The reciprocal cross gives a different result. A reciprocal cross between white-eyed females and red-eyed males gives an F1 in which all the females are red eyed, but all the males are white eyed.
What gene is mutated in the white-eyed flies?
The Drosophila gene w (CG2759) is a central part of the eye-pigmentation pathway. It encodes an ATP binding cassette transporter, White (O’Hare et al., 1984; Pepling and Mount, 1990), that forms dimers with either Brown or Scarlet proteins, encoded by brown and scarlet genes respectively.
What is the genotype of the white-eyed male?
The male is hemizygous for both the recessive (white) eye color allele and dominant (tan) body color allele. His genotype is Xwy+ Y.