Question

can someone verify this?

In Drosophila, alternate alleles of an X chromosome gene, white, determine red eyes (w') and white eyes (w). Alternate alleles of a second X chromosome gene, yellow, determine brown body ) and yellow body (). In cross series A and B, the F1 females are heterozygous for both genes, but the arrangement of alleles in the parental generation is different in each case. Study the genotypes and phenotypes of the P, F1, and F2 flies in the diagrams of cross A and B. Label the phenotypes of the P generation and F2 males, and determine if the F2 males are parental or recombinant. Each choice will be used more than once. Recombinant Eye color Parental Body color Cross Series A Cross Seri brown * - 9 - $ red white +3 F2 males F2 males yellow Parental or recombinant Parental Parental Recombinant Recombinant Parental Parental Eye color .

Answer 1

According to question, w⁺ is for red eyes and w is for white eyes. y⁺ is for brown body and y is for yellow body.

In F2 results, the offsprings with genotype as parents (Male or female) would be considered to have parental combination while those with new allele combinations would be considered as recombinant. Males have one X chromosome so they have one allele for eye color and body color.

Cross series A

Female parent- genotype: wwy⁺y⁺

   phenotype: white eyes, brown body

Male parent- genotype : w⁺y Y

Phenotype:Red eyes , yellow body

Phenotype of F2 males :

1. wy⁺ - white eyes, brown body (parental combination)

2. w⁺y - red eyes yellow body ( parental combination)

3. wy - white eyes , yellow body ( recombinant)

4. w⁺y⁺ - red eyes brown body (recombinant)

Cross section B

Female parent- w⁺w⁺y⁺y⁺ - red eyes, brown body

Male parent- wy Y - white eyes, yellow body

Phenotype of F2 males

1. w⁺y⁺ - red eyes, brown body (parental combination)

2. wy - white eyes, yellow body (parental combination)

3. w⁺y - red eyes, yellow body (recombinant)

4. wy⁺ - white eyes, brown body (recombinant)