Sex-Linked Inheritance - Haemophilia, Colour Blindness - Unsolved Practice Set
Chapter: Principles of Inheritance and Variation | Topic: Sex Linked Inheritance Haemophilia Colour Blindness
SEX-LINKED INHERITANCE - HAEMOPHILIA, COLOUR BLINDNESS - UNSOLVED PRACTICE SET
Topic: Sex Linked Inheritance Haemophilia Colour Blindness
Multiple Choice Questions
Q1. Genes located on the X chromosome, showing a characteristic inheritance pattern different from autosomal genes, are said to be:
- Autosomal
- Sex-linked
- Cytoplasmic
- Mitochondrial
Q2. Haemophilia and red-green colour blindness in humans are both examples of:
- Autosomal dominant disorders
- X-linked recessive disorders
- Y-linked disorders
- Codominant disorders
Q3. A woman who carries one recessive allele for haemophilia on one of her X chromosomes but does not show the disease herself is called a:
- Affected female
- Carrier female
- Unaffected male
- Non-carrier
Q4. X-linked recessive disorders like haemophilia are more commonly observed in:
- Females than males
- Males than females
- Equally in males and females
- Neither sex
Q5. The pattern in which an X-linked recessive trait passes from a carrier mother to her sons is often called:
- Blending inheritance
- Criss-cross inheritance
- Codominant inheritance
- Polygenic inheritance
Short Answer Questions
Q6. Why are X-linked recessive disorders like haemophilia more commonly seen in males than in females?
Q7. What is a "carrier female" in the context of X-linked inheritance? Give an example.
Q8. Briefly explain what is meant by the "criss-cross inheritance" pattern.
Q9. Name two common X-linked recessive disorders found in humans.
Long Answer Questions
Q10. Explain the inheritance pattern of haemophilia in humans, describing how a carrier mother can have an affected son even if the father is unaffected.
Q11. Discuss why red-green colour blindness shows a higher prevalence in males compared to females, using the concept of X-linked recessive inheritance.
APPLICATION / ANALYSIS
Q12. A woman who is a known carrier for haemophilia marries a man who does not have haemophilia. Work out the possible genotypes and phenotypes of their children with respect to haemophilia, and explain your reasoning.
Q13. In a family, a colour-blind father and a mother who is not a carrier for colour blindness have children. Predict whether their daughters and sons are likely to be colour blind, carriers, or unaffected, explaining your answer using X-linked inheritance principles.