Incomplete and Codominance Worksheet 1. Explain the difference between incomplete dominance and codominance: Incomplete Dominance 2. In snapdragons, flower color is controlled by incomplete dominance. The two alleles are red (R) and white (W). The heterozygous genotype is expressed as pink. a. What is the phenotype of a plant with the genotype RR? ___________ b. What is the phenotype of a plant with the genotype WW? ___________ c. What is the phenotype of a plant with the genotype RW? ___________ Codominance 3. In some chickens, the gene for feather color is controlled by codiminance. The allele for black is B and the allele for white is W. The heterozygous phenotype is known as erminette . a. What is the genotype for black chickens? _______________________________ b. What is the genotype for white chickens? _______________________________ c. What is the genotype for erminette chickens? ____________________________ Chapter 4 Review Questions 4. Two pea plants with yellow peas were crossed, and the seeds were planted. Of the 100 offspring, 73 had yellow peas, and the other 27 had green peas. Which allele is dominant? 5. Identify each of the results of these purebred crosses as an example of simple dominance, incomplete dominance, or codominance. a. _________________ A purebred pea plant with wrinkled seeds is pollinated with a purebred pea plant with round seeds. All of the offspring have round seeds. b. _________________A mom with type A blood and a dad with type B blood have a child with type AB blood. c.__________________A purebred white poppy is pollinated by a purebred red poppy. All of the offspring have pink blossoms. d.__________________A purebred white sheep is bred with a purebred red poppy. All of the offspring have pink blossons. 6. A white albino rabbit lacks fur color. It carries the alleles rr. What is its genotype and phenotype? 7. Human blood type involves what kind of inheritance?
