Unit 5 Chapter 11 Fundamentals of Genetics Section 11.1 Mendel’s Legacy

I) Gregor Mendel Genetics: study of how traits & characteristics are transferred from parent to offspring Gregor Mendel: “Father of Genetics” Combined Plant breeding Statistics Careful recordkeeping

II) Mendel’s Experiment Mendel experiment garden peas with 7 characteristics to see which trait would be passed to offspring Traits: specific inherited characteristics Example: Characteristic: Plant Height Trait: Tall or Short

II) Mendel’s Experiments Mendel started growing peas that were pure for each trait Pure: one has genetic information for one trait Example: Pure breed dogs Mendel self-pollinated the peas until he obtained pure samples

II. Mendel’s Experiment 4. Mendel controlled the reproduction of the plants through pollination 5. Pollination: pollen from reproductive parts of one flower is mixed w/ another flower -Self-pollination: mixing with the same plant/flower from same seed -Cross-pollination: mixing pollen with a different plant/flower from a different seed

II. Mendel’s Experiments 8. Cross Pollinated: Ex: Characteristic: Plant Height Trait: Short x Tall Mendel recorded the results & called the offspring the F1 generation

III) Mendel’s Results and Conclusions There was a “factor” in pea controlling the traits Results varied between 2 traits he felt that the “factor” came in pairs (1 from mom and 1 from dad)

Mendel’s Experiment Parent generation: Pure Green, Pure Yellow Pure Green x Pure Yellow = F1 generation F1 generation: All Green F1 gen. x F1 gen. = F2 generation Green x Green = 3 Green + 1 Yellow F2 generation: 3 Green + 1 Yellow

III. Recessive and Dominant Traits Mendel saw that one parent trait would not show in the F1, and reappear in F2 Dominant: factor that would dominated and mask the other trait Recessive: factor that could be masked by a dominant trait

IV. Mendel’s Laws Law of Segregation: a pair of factors is segregated, or separated, during the formation of gametes (sperm and egg cells) Law of Independent Assortment: factors for different characteristics are distributed to gametes(sperm and egg cells) independently

V. Genes Genes are in pairs or alleles Alleles are represented by letters Dominant: Uppercase Recessive: Lowercase