8. Suppose a father of blood type A and a mother of blood type B have a child of type O. What blood types are possible in their subsequent children?

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1 1. Use the Punne, square to determine all of the offspring genotypes (and their rela;ve frequencies) from the following crosses: a. Rr x Rr b. Rr x rr c. RR x Rr In the problem above, the "R" allele is a dominant allele specifying for round seeds (in peas), while the "r" allele is the recessive allele specifying for wrinkled seeds. Give the expected frequencies (as percentages or ra;os) for the phenotypes of the offspring resul;ng from each of the crosses above. 2. A brown mink crossed with a silverblue mink produced all brown offspring. When these F1 mink were crossed among themselves they produced 47 brown animals and 15 silverblue animals (F2 genera;on). Determine all the genotypes and phenotypes, and their rela;ve ra;os, in the F1 and F2 genera;ons.

2 3. In sheep white is due to a dominant gene (W), black to its recessive allele (w). A white ewe mated to a white ram produces a black lamb. If they produce another offspring, could it be white? If so, what are the chances of it being white? List the genotypes of all animals men;oned in this problem. 4. In tomatoes the texture of the skin may be smooth or peach (hairy). The Ponderosa variety has fruits with smooth texture. The red peach variety has fruits with peach texture. Crosses between the two varie;es produce all smooth fruits. Crosses between these smooth fruited F1 plants produced 174 peach textured fruits and 520 smooth textured fruits. How are these skin textures inherited? complete dominante

3 5. A brown mouse is mated is mated with two female black mice. When each female has produced several li,ers of young, the first female has had 48 black and the second female has had 14 black and 11 brown young. Deduce the pa,ern of inheritance of coat color and the genotypes of all of the parents. 6. ellow guinea pigs crossed with white ones always produce cream colored offspring. Two cream colored guinea pigs when crossed produced yellow, cream and white offspring in the ra;o of l yellow: 2 cream: l white. How are these colors inherited?

4 7. In humans the blood groups are produced by various combina;ons of three alleles I A, I, and i. lood type A is caused by either I A I A or I A i; type by I I or I i; type A by I A I ; and type O by i i. Suppose a child is of blood type A and the mother is of type 0. What type or types may the father belong to? 8. Suppose a father of blood type A and a mother of blood type have a child of type O. What blood types are possible in their subsequent children?

5 9. Suppose a father of blood type and a mother of blood type O have a child of type O. What are the chances that their next child will be blood type O? Type? Type A? Type A? 10. Suppose a father and mother claim they have been given the wrong baby at the hospital. oth parents are blood type A. The baby they have been given is blood type O. What evidence bearing on this case does this fact have?

6 11. A mother and father with normal color vision produce six male children, two of whom exhibit red- green colorblindness. Their five female children exhibit normal color vision. Explain the inheritance of red- green colorblindness in their male children. 12. Prac;ce secng up keys for the phenotypes listed in each set. a) irds can be blue, white, or white with blue- ;pped feathers. b) Flowers can be white, pink, or red. c) A Hoo can have curly hair, spiked hair, or a mix of both curly and spiked. d) A Sneech can be tall, medium, or short. e) A leexo can be spo,ed, black, or white. Now, can you figure out in the above list, which of the le,ers represent codominant traits and which are incomplete. Codominant Incompletely Dominant

7 13. In Smileys, eye shape can be starred, circular, or a circle with a star. Write the genotypes for the pictured phenotypes Show the cross between a star- eyed and a circle eyed. What are the phenotypes of the offspring? What are the genotypes? Show the cross between a circle- star eyed, and a circle eyed. How many of the offspring are circle- eyed? How many of the offspring are circle- star eyed? Show the cross between two circle- star eyed. How many of the offspring are circle- eyed? How many of the offspring are circle- star eyed? How many are star eyed? 14. **In fruit flies, eye color is a sex linked trait. Red is dominant to white.** What are the sexes and eye colors of flies with the following genotypes? R r R r r R R r What are the genotypes of these flies: white eyed, male red eyed female (heterozygous) white eyed, female red eyed, male Show the cross of a white eyed female r r with a red- eyed male R. Show a cross between a pure red eyed female and a white eyed male. What are the genotypes of the parents: and How many are: white eyed, male white eyed, female red eyed, male red eyed, female Show the cross of a red eyed female (heterozygous) and a red eyed male. What are the genotypes of the parents? & How many are: white eyed, male white eyed, female red eyed, male red eyed, female What if in the above cross, 100 males were produced and 200 females. How many tota red- eyed flies would there be?

8 15. Human Sex Linkage 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) H H = female, normal H h = female, carrier h h = female, hemophiliac H = male, normal h = male, hemophiliac Show the cross of a man who has hemophilia with a woman who is a carrier. What is the probability that their children will have the disease? A woman who is a carrier marries a normal man. Show the cross. What is the probability that their children will have hemophilia? What sex will a child in the family with hemophilia be? A woman who has hemophilia marries a normal man. How many of their children will have hemophilia, and what is their sex? 16. Calico Cat Gene/cs In cats, the gene for calico (mul9colored) cats is codominant and sex- linked. Females that receive a and an R gene have black and orange splotches on white coats. Males can only be black or orange, but never calico. Here s what a calico female s genotype would look like: R R Show the cross of a female calico cat with a black male? R R What percentage of the kimens will be black and male? 25% What percentage of the kimens will be calico and male? 0% What percentage of the kimens will be calico and female? 25% Show the cross of a female black cat, with a male orange cat. /2 (for cross and %) R R R What percentage of the kimens will be calico and female? _50%_What color will all the male cats be? lack /2 (for cross and %)

9 Not counted /36.5