Question

Morgan demonstrated that white eye color in Drosophila is carried recessively on the X chromosome (females are XX and males are XY). Which of the following best describes the offspring of a heterozygous (carrier) female and a white-eyed male?

a. All offspring will have white eyes.
b. All offspring will have red eyes.
c. All offspring will be carriers.
d. Half of the offspring will have white eyes, and half will be carriers.

Answer 1

The correct description of the offspring of a heterozygous female and a white-eyed male Drosophila is that half of the offspring will have white eyes, and half will be carriers.

Step-by-step explanation:

X-linked Inheritance in Drosophila

In the case of X-linked inheritance in Drosophila, a cross between a heterozygous (carrier) female, denoted as XWXw, and a white-eyed male, denoted as XwY, leads to the following offspring:

• 50% of the males will be hemizygous with white eyes (XwY).
• 50% of the males will be hemizygous with red eyes (XWY).
• 50% of the females will be heterozygous with red eyes (XWXw).
• 50% of the females will be homozygous with white eyes (XwXw).

Therefore, the correct answer to the question, "Which of the following best describes the offspring of a heterozygous (carrier) female and a white-eyed male?" is that half of the offspring will have white eyes, and half will be carriers.