Sex Linked Traits

Decode sex-linked traits! Practice genetics problems & Punnett squares on X-linked inheritance.

1. Sex-linked traits are linked on which chromosome? X Y both X and Y 2. What are most sex-linked traits? dominant recessive neither dominant or recessive both dominant and recessive 3. What is the genotype of a male? X XX XY YY 4. What is the genotype of a female? X XX XY YY 5. Who is most likely to be a carrier of a sex-linked trait? females males females and males are affected equally 6. Problem 1 Colorblindness is a recessive trait. If a female heterozygousfor red-green color blindness and a male who has normal color vision have a child what is the probability of their male and female children being color blind? Perform the cross below and then answer questions 7 and 8. * Use B for your trait letter. * Use XB or Xb when putting your letters on the square.* Your female goes at the top of the square in order for this to score you correctly. XBXB XB XB Y XBY XbY XBXb Xb 7. What percent of their male children would be colorblind? 0% 25% 50% 100% 8. What percent of their female children would not be colorblind? 0% 25% 50% 100% 9. Problem 2 Hemophilia is a sex-linked recessive trait whereas blood-clotting is a dominant trait.A homozygous normal blood-clotting female marries a male who has hemophilia. Create the Punnett Square and answer question 10. * Use H for the traits.*Use XH and Xh when putting your letters on the square.* Remember, the female goes at the top of the square XH Xh Y XHY XHY XHXh XH XHXh 10. What are the possibilities for the offspring of these two parents? 2 normal blood clotting females, 2 hemophilia males 2 carrier females, 2 hemophilia males 2 normal blood clotting females, 2 normal blood clotting males 2 carrier females, 2 normal blood clotting males 11. The Punnett Square pictured shows the cross between two fruit flies. A heterozygous female with red eyes and a white-eyed male.Your task is to identify the phenotypes of the offspring. Type in your answer. 12. EXPLAIN whether males and females are more likely to get a sex-linked disorder.