Survey
* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project
Download Genetics: Sex-Linked Traits
Document related concepts
no text concepts found
Transcript
Name: __________________________________ Date: __________ Period: _____ Genetics: Sex-Linked Traits! In fruit flies, eye color is a sex linked trait. Red (R) eyes are dominant to white (r) eyes. 1. Since the characteristic is sex-linked, on which chromosome (X or Y) will the allele for fly eye color be located? _______ 2. What are the sexes and eye colors of flies with the following genotypes? XRXr sex: ________ eye color:___________ XRY sex: ________ eye color:___________ XRXR sex: ________ eye color:___________ XrY sex: ________ eye color:___________ 3. What are the genotypes of these flies? white eyed, male ____________ white eyed, female ___________ 4. Show the cross of a white eyed female (X r red eyed female (heterozygous) ________ red eyed, male ___________ X r ) with a red-eyed male (X R Y) . 5. What are the possible genotypes of the male offspring? ________________________ 6. What are the possible genotypes of the female offspring? _______________________ 7. What are the possible phenotypes of the male offspring? ________________________ 8. What are the possible phenotypes of the female offspring? _______________________ 9. Let’s now perform a cross between a pure red eyed female and a white eyed male! a. What are the genotypes of the parents? ___________& ____________ b. Complete the cross. What is the possibility that the offspring are: white eyed, male_____ red eyed, male ______ white eyed, female _____ red eyed, female ______ 10. Show the cross of a red eyed female (heterozygous) and a red eyed male. a. What are the genotypes of the parents? ___________& ____________ b. Complete the cross. What is the possibility that the offspring are: white eyed, male_____ red eyed, male ______ white eyed, female _____ red eyed, female ______ Name: __________________________________ Date: __________ Period: _____ 11. In humans, hemophilia is a sex linked trait. Females can be normal, carriers, or have the disease. Males will either have the disease or not (but they won’t ever be carriers). = female, normal = male, normal = female, carrier = male, hemophiliac = female, hemophiliac 12. Show the cross of a man who has hemophilia with a woman who is a carrier. 13. What is the probability that their children will have the disease? __________ 14. A woman who is a carrier marries a normal man. Show the cross. What is the probability that their children will have hemophilia? 15. A woman who has hemophilia marries a normal man. How many children, out of 4, would you predict to have hemophilia? What is(are) the sex(es) of the child(ren) born with the disease? Name: __________________________________ Date: __________ Period: _____ BONUS PROBLEMS: Sex-Linked Traits! In cats, the alleles for calico (multicolored) cats are co-dominant. This means that if both of the possible alleles are inherited, they will both be expressed. When considering the gene for calico cats, one allele is NOT more dominant than the other. Therefore, we will NOT use the same letter to represent these alleles, because one trait isn’t dominant. In cats, B = black fur color, O = orange fur color. 1. In addition, the genes for calico cats are sex-linked. Since they are sex-linked, on which chromosome are the alleles for cat fur color found? __________ Therefore, an allele that codes for black fur would look like this: _________ and an allele that codes for orange fur color would look like this: __________ CALICO CAT BLACK CAT ORANGE CAT Female cats that receive a B and an O gene have black and orange splotches on their white fur coats. Their GENOTYPE would look like this: X B X O. Males can only be black or orange, but never calico. 2. How come male cats cannot be calico? Explain using at least three sentences. 3. Show the cross of a female calico cat with a black male cat! What percentage of the kittens will be black and male? _________ What percentage of the kittens will be calico and male? _________ What percentage of the kittens will be calico and female? _________ 4. Show the cross of a female black cat with a male orange cat! What percentage of the kittens will be calico and female? _____ Fill in the blank: All the male cats will have _____________ color fur.
Related documents