Sex Determination - XX-XY, ZZ-ZW - Unsolved Practice Set
Chapter: Principles of Inheritance and Variation | Topic: Sex Determination XX XY ZZ ZW
SEX DETERMINATION - XX-XY, ZZ-ZW - UNSOLVED PRACTICE SET
Topic: Sex Determination XX XY ZZ ZW
Multiple Choice Questions
Q1. In humans, the sex of an offspring is genetically determined by the chromosome contributed by the:
- Mother always
- Father, specifically whether the sperm carries an X or Y chromosome
- Environment
- Grandparents
Q2. The XX-XY type of sex determination is seen in:
- Birds
- Humans and Drosophila
- Honeybees
- Grasshoppers only
Q3. In birds, males are typically:
- XY
- XX
- ZZ
- ZW
Q4. In the ZW-ZZ system, the female is:
- ZZ
- ZW
- XX
- XY
Q5. In honeybees, sex is determined by a mechanism called:
- XY system
- ZW system
- Haplodiploidy (based on chromosome number, not sex chromosomes)
- XO system
Short Answer Questions
Q6. Explain briefly why, in humans, it is the father's chromosome contribution that determines the sex of the child, and not the mother's.
Q7. Differentiate between the XY and ZW systems of sex determination, mentioning one example organism for each.
Q8. What is the XO type of sex determination? Name one organism showing this pattern.
Q9. What are autosomes, and how are they different from sex chromosomes?
Long Answer Questions
Q10. Describe the chromosomal basis of sex determination in humans, explaining how the combination of sex chromosomes in the sperm and egg determines the sex of the child.
Q11. Compare the XY, ZW, and XO systems of sex determination, highlighting the key differences between them.
APPLICATION / ANALYSIS
Q12. A couple already has three daughters and is hoping for a son. The husband is often blamed by relatives for "not producing a son." Using your understanding of human sex determination, explain the biological reasoning that shows this blame is scientifically incorrect.
Q13. In a certain species of bird, all sons resemble their mother's specific plumage pattern more closely than expected from typical autosomal inheritance. Considering that birds follow the ZW system of sex determination, suggest a possible explanation involving the Z chromosome for this pattern.