Which of the following observations support the idea that the gene controlling maleness is located on the Y chromosome?
A) XO individuals are usually sterile, normal intelligence, female, with slight physical abnormalities.
B) XXY individuals are sterile males with long limbs.
C) XXX individuals are normal females.
D) Some men are XX but have a small piece of the Y attached to another chromosome.
E) All of the above are observations suggesting that the gene controlling maleness is on the Y chromosomes.

Question

Which of the following observations support the idea that the gene controlling maleness is located on the Y chromosome?
A) XO individuals are usually sterile, normal intelligence, female, with slight physical abnormalities.
B) XXY individuals are sterile males with long limbs.
C) XXX individuals are normal females.
D) Some men are XX but have a small piece of the Y attached to another chromosome.
E) All of the above are observations suggesting that the gene controlling maleness is on the Y chromosomes.

Quizplus · Accepted Answer

The presence of a Y chromosome is necessary for maleness. XO individuals are female because they lack a Y chromosome. XXY individuals are male because they have a Y chromosome, but they are sterile because they have an extra X chromosome. XXX individuals are female because they have three X chromosomes. Some men are XX but have a small piece of the Y chromosome attached to another chromosome. This is called a translocation. The presence of the Y chromosome, even a small piece of it, is necessary for maleness.

Which of the Following Observations Support the Idea That the Gene