1. Ducks of the breed “Swedish Blue” have grey plumage. If two Swedish Blue ducks mate then some of the offspring produced are grey, some black and some white. Explain these observations and describe how a poultry breeder cold ensure that he produces all grey ducks.

2. In Shorthorn cattle the gene for coat colour has two alleles, CW which codes for white hair and CR which codes for red hair. The alleles are co dominant. Heterozygous individuals have a mixture of white and red hairs and their coat colour is described as roan. A shorthorn bull is mated with several red cows. 11 of the offspring produced are red and 10 roan. What is the genotype and phenotype of the bull?

4. In Peas the gene for flower colour (purple or red) is on the same chromosome as the gene for pollen grain shape (long or short) Flower Purple = FP (dominant) Red = Fr (recessive) Pollen grain shape Long = GL (dominant) Short = Gl (recessive)

5. In Peas the gene for height (tall of dwarf) is on the same Chromosome as the gene for seed pod texture (smooth or wrinkled) Height Tall = HT (dominant) Dwarf = Ht (recessive) Seed pod texture Smooth = PM (dominant) Wrinkled = Pm (recessive) What would be the offspring of two plants one homozygous recessive, one heterozygous?

6. In tomatoes the gene for flower colour (white or yellow) is on the same chromosome as the fruit colour (red or yellow) plants with white flowers have yellow fruit and plants with yellow flowers have red fruit. Fruit Red = R (dominant) yellow = r (recessive) Flower Yellow = Y (dominant) White = y (recessive) What would be the offspring of two plants one homozygous recessive, homozygous dominant? What ratios of genotypes and phenotypes would you expect to see in the offspring if these offspring are all owed to interbred? Why will a few of the offspring differ from the expected phenotypes?

7. In humans the gene for tongue rolling (T or t) and the gene for ability to taste PTC (P or p) are not linked. They are found on different chromosomes. • If one parent is homozygous recessive for both characteristics and the other is heterozygous for both characteristics then what are the possible genotypes and phenotypes of their children?

8. In humans the gene for tongue rolling (T or t) and the gene for ability to taste PTC (P or p) are not linked. They are found on different chromosomes. • If one parent is homozygous recessive for both characteristics and the other is heterozygous for both characteristics then what are the possible genotypes and phenotypes of their children? • One parent has the genotype Tt pp, the other tt Pp, What are the possible genotypes and phenotypes of their children?

9. In peas the gene for seed colour (G = green g = yellow) and the gene for seed texture (R = round r = wrinkled) are not linked. They are found on different chromosomes. • If one parent has yellow, wrinkled seeds, the other has Green round seeds. Some of the offspring have yellow, wrinkled seeds. • What is the genotype of the parent plant with green, round seeds? • Out of 100 offspring how many would you expect to have yellow, wrinkled seeds?