Home
Class 12
BIOLOGY
A couple had two sons, one was colour bl...

A couple had two sons, one was colour blind while the other wasn't. They also had a colour blind daughter. Which statement about this couple is true?

A

Husband is colour blind but wife is not

B

Husband is normal and wife is colour blind

C

Husband and wife both are colour blind

D

Husband and wife both are normal

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question regarding the couple and their children with color blindness, we need to analyze the genetic inheritance of color blindness, which is a sex-linked recessive trait. Here’s a step-by-step breakdown of the solution: ### Step 1: Understand the Genetics of Color Blindness Color blindness is a recessive trait linked to the X chromosome. This means that males (XY) are more likely to express color blindness because they have only one X chromosome. Females (XX) can be carriers if they have one normal X chromosome and one affected X chromosome. ### Step 2: Identify the Traits of the Children The couple has: - Two sons: One is color blind and the other is not. - One daughter: She is color blind. ### Step 3: Determine the Father's Genotype Since one son is color blind, the father must have the color blind trait. Therefore, the father's genotype is: - X^hY (where X^h represents the color blind allele). ### Step 4: Determine the Mother's Genotype The mother must be a carrier because: - She has a color blind daughter (who must inherit one affected X from her). - She must also have a normal X to pass on to the son who is not color blind. Thus, the mother's genotype is: - X^HX^h (where X^H represents the normal allele). ### Step 5: Analyze the Children’s Genotypes From the parents' genotypes: - The color blind son (X^hY) receives the X^h from the mother and Y from the father. - The normal son (X^HY) receives the X^H from the mother and Y from the father. - The color blind daughter (X^hX^h) receives X^h from both parents (one from the father and one from the mother). ### Step 6: Conclusion About the Couple Based on the analysis: - The father is color blind (X^hY). - The mother is a carrier (X^HX^h). Thus, the correct statement about this couple is: "The husband is color blind, but the wife is not (she is a carrier)." ### Summary of the Correct Statement - The husband is color blind, and the wife is a carrier. ---
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • NTA NEET SET 107

    NTA MOCK TESTS|Exercise BIOLOGY|90 Videos

  • NTA NEET SET 109

    NTA MOCK TESTS|Exercise BIOLOGY|90 Videos

Similar Questions

Explore conceptually related problems

A man whose father was colour blind marries a woman who had a colour blind mother and normal father. What percentage of male children of this couple will be colour blind?

A man whose father was colour blind marries a woman who has a colour blind mother and normal father .What percentage of male childern of this couple will be colour blind ?

Knowledge Check

  • Which sttement about colour blindness is correct

    A
    6% men are red colour blind, 2% are green colou blind
    B
    2% men are red colour blind , 6% are green colour blind
    C
    10% men are red colour blind , 5% are green colour blind
    D
    5% men are red colour blind ,10% are green colour blind.

  • A man whose father was colour blind marries a woman who had a colour blind mother and normal father. What percentage of male children of this couple will be colour blind

    A
    0.5
    B
    0.75
    C
    0.25
    D
    0

  • A man whose father was colour blind marries a woman who had a colour blind mother and normal father. What percentage of male children of this couple will be colour blind ?

    A
    `25%`
    B
    `0% `
    C
    `50%`
    D
    `75%`

    • Similar Questions

    Explore conceptually related problems

    A colour blind man marries a daughter of normal woman and colour blind man.the ratio of carrier daughter,colour blind daughters,normal sons born to this couple wil be ,

    A man whose father was colour blind marries a woman who had colour blind mother and normal father what precentage of male childeren of this couple will be colour blind

    A colour - blind man has a colour - blind sister but a. normal brother. Which of these is correct about their parents ?

    A normal-visioned man whose father was colour-blind, marries a woman whose father was also colour-blind. They have their first child as a daughter. What are the chances that this child would be colour-blind

    A normal-visioned man whose father was colour-blind, marries a woman whose father was also colour-blind. They have their first child as a daughter. What are the chances that this child would be colour-blind?

    Home
    Profile