1. More Mendelian Genetics and Mendel’s Laws

2. Vocabulary True-breeding: a plant that always produces offspring with identical traits when it self-pollinates Hybrid: the offspring of plant parents with different traits Segregation: separation Independent assortment: the fact that genes for different traits end up in gametes independently of other traits. For example, your genes for hair color do not influence what genes you will get for your eye color.

3. Vocabulary Codominance: when two alleles are equally dominant, so both traits appear. An example of this is ABO blood tying. O is recessive to both A and B, so AO = type A blood and BO = type B blood. A and B are codominant, so both A and B appear in the phenotype. AB alleles = type AB blood Incomplete dominance: when neither of the two alleles is truly dominant over the other, so the traits blend. An example is flower color in snapdragons. Red flowers x white flowers = pink flowers

4. Codominance In ABO blood typing, both A and B are dominant to O, but A and B are codominant to each other. When both A and B alleles are present, a person’s blood type is AB.

5. Incomplete Dominance In snapdragons, the red and white alleles for flower are incompletely dominant to each other. RR = red WW = white RW = pink

6. Check for Understanding Complete this Punnett square. Parent 1 is a snapdragon with red flowers, and parent 2 is a snapdragon with pink flowers. What is the ratio of genotypes? What is the ratio of phenotypes?

7. Mendel’s Law of Segregation

9. Mendel’s Law of Independent Assortment

10. What this really means is that trait do not affect each other: they are assorted into different gametes independently of each other. For example, having a hitchhiker’s thumb has no influence on the shape of your chin. Note: Some genes are linked, that is, they are on the same chromosome and tend to be inherited together, like red hair and freckles. We will not worry about these genes for now.

11. Bozeman Video Mendel’s Peas and the Laws of Segregation and Independent Assortment