In humans, blue eyes are inherited as a recessive autosomal trait and color blin
ID: 20789 • Letter: I
Question
In humans, blue eyes are inherited as a recessive autosomal trait and color blindness is an X-linked recessive trait. A woman with blue eyes and normal color vision whose father was color blind marries a man who also has normal color vision. He has brown eyes, but his mother had blue eyes. Which of the following do you expect to be true for their sons?One-half of their sons will be color blind and have blue eyes; 1/2 their sons will be color blind and have brown eyes.
One-fourth of their sons will be color blind and have blue eyes, 1/4 of their sons will be color blind and have brown eyes, 1/4 of their sons will have normal color vision and blue eyes, 1/4 of their sons will have normal color vision and brown eyes.
Their sons will all have normal color vision and blue eyes.
Their sons will all have normal color vision and brown eyes.
One-half of their sons will have normal color vision and brown eyes; 1/2 of their sons will have normal color vision and blue eyes.
Explanation / Answer
In humans, blue eyes are inherited as a recessive autosomal trait and color blindness is an X-linked recessive trait.
A woman with blue eyes and normal color vision whose father was color blind marries a man who also has normal color vision. He has brown eyes, but his mother had blue eyes. Which of the following do you expect to be true for their sons?
One-half of their sons will be color blind and have blue eyes; 1/2 their sons will be color blind and have brown eyes.
One-fourth of their sons will be color blind and have blue eyes, 1/4 of their sons will be color blind and have brown eyes, 1/4 of their sons will have normal color vision and blue eyes, 1/4 of their sons will have normal color vision and brown eyes.
Their sons will all have normal color vision and blue eyes.
Their sons will all have normal color vision and brown eyes.
One-half of their sons will have normal color vision and brown eyes; 1/2 of their sons will have normal color vision and blue eyes.
blue eyes are inherited as a recessive autosomal trait
color blindness is an X-linked recessive trait.
A woman with blue eyes and normal color vision--------genotype---------bbXCX
man brown eyes, AND normal color vision-------------------genotype---------BbXY
BX
BY
bX
bY
bXC
bXC BX
brown eyes,
female
bXC BY
brown eyes,
male
colorblind
bXC bX
blue eyes female
bXC bY
blue eyes
male
colorblind
bXC
bXC BX
brown eyes, female
bXC BY
brown eyes, male
colorblind
bXCBx
blue eyes female
bXC bY blue eyes male
colorblind
bX
bX BX
brown eyes, female
bX BY
brown eyes, male
bX bX
blue eyes female
bX bY blue eyes male
bX
bX BX
brown eyes, female
bX BY
brown eyes,
male
bX bX
blue eyes female
bX bY blue eyes male
BX
BY
bX
bY
bXC
bXC BX
brown eyes,
female
bXC BY
brown eyes,
male
colorblind
bXC bX
blue eyes female
bXC bY
blue eyes
male
colorblind
bXC
bXC BX
brown eyes, female
bXC BY
brown eyes, male
colorblind
bXCBx
blue eyes female
bXC bY blue eyes male
colorblind
bX
bX BX
brown eyes, female
bX BY
brown eyes, male
bX bX
blue eyes female
bX bY blue eyes male
bX
bX BX
brown eyes, female
bX BY
brown eyes,
male
bX bX
blue eyes female
bX bY blue eyes male