Question

In fruit flies eye color is a sex linked trait where red eyes are dominant to the white eye phenotype. If a male with red eyes is crossed with a purebred white eye female, what is the ratio of eye color and sex phenotypes for their offspring?

A. 1 red eye female : 0 white eye female: 0 red eye male : 1 white eye male

B. 2 red eye female : 1 white eye female: 0 red eye male : 1 white eye male

C. 1 red eye female : 1 white eye female: 1 red eye male : 1 white eye male

D. 0 red eye female : 1 white eye female: 1 red eye male : 0 white eye male

If you answer the incorrect answer I will report you!

Answer 1

Answer:

2 red eye females : 2 white eye males

Explanation:

The ratio of eye color and sex phenotypes for their offspring would be 2 red eye females : 2 white eye males.

Let the allele for eye color be represented by A (red eye) and the alternate form a (white eye).

In fruitfly, XY individuals are males while XX are females.

Hence;

A male with red eye will have the genotype - $X^AY$

A purebred white eye female will have the genotype - $X^aX^a$

Crossing the male and the female:

$X^AY$   x   $X^aX^a$

Progeny: $X^AX^a, X^AX^a, X^aY, X^aY$

Phenotypes of the progeny:

2 $X^AX^a$ - red eye, females

2 $X^aY$ - white eye, males.

The ratio of eye color and sex phenotypes of their offspring are 2 red eye females : 2 white eye males

Answer 2

Answer:

2 red eye females : 2 white eye males

Explanation:

The ratio of eye color and sex phenotypes for their offspring would be 2 red eye females : 2 white eye males.

Let the allele for eye color be represented by A (red eye) and the alternate form a (white eye).

In fruitfly, XY individuals are males while XX are females.

Hence;

A male with red eye will have the genotype -

A purebred white eye female will have the genotype -

Crossing the male and the female:

  x  

Progeny:

Phenotypes of the progeny:

2  - red eye, females

2  - white eye, males.

The ratio of eye color and sex phenotypes of their offspring are 2 red eye females : 2 white eye males

Explanation: