Set up Cornell Notes on pg. 75 Topic: 7.2 Patterns of Inheritance Essential Questions: Why might polygenic traits vary more in phenotype than do single-gene traits? How is codominance the same as having no dominant and recessive relationship at all between 2 alleles? 7.2 Patterns of Inheritance 2.1 Atoms, Ions, and Molecules Why might polygenic traits vary more in phenotype than do single-gene traits? How is codominance the same as having no dominant and recessive relationship at all between 2 alleles? KEY CONCEPT Phenotype is affected by many different factors.

KEY CONCEPT Phenotype is affected by many different factors.

+ What are our possible outcomes for this combination of flower color? What if red nor white was dominant or recessive to one another?

In incomplete dominance, neither allele is completely dominant nor completely recessive. They are a BLEND of each other Ex: red+white rose= pink rose BB RR BR

B B BR BR R BR BR R Genotype: Phenotype: BR 100% pink flowers

B R B R BB Red rose BR Pink rose BR Pink rose RR White rose Genotype: BB= red RR= white BR= pink Phenotype: 25%= red flowers 50%= pink flowers 25%= white flowers

Codominant alleles will both be completely expressed. Codominant alleles are neither dominant nor recessive. Ex: multi-colored red and white rose

B B BR BR R BR BR R Genotype: Phenotype: BR 100% red and white flowers

Polygenic traits are produced by two or more genes. Can produce a continuous range of colors Ex: Skin color- 4 genes Eye color- at least 3 genes