The document discusses Mendel's experiments on dihybrid crosses. It explains that Mendel crossed pure-breeding plants that differed in two traits - plant height and flower color. In the F1 generation, all offspring exhibited the dominant traits of tall height and purple flowers. When the F1 plants were self-crossed, the F2 generation showed a 9:3:3:1 ratio of phenotypes. This supported Mendel's law of independent assortment, which states that two traits segregate independently during gamete formation.

1. LECTURE 3

7. P : Tall colored x Dwarf white TTCC ttcc G : all TC all tc F1 : Tall colored x Tall colored TtCc TtCc G : ¼TC ¼Tc ¼ tC ¼tc ¼TC ¼Tc ¼ tC ¼tc Segregation with independent assortment F2 : Punnett square

8.  ttCc  ttcc Tall colored Tall white dwarf colored dwarf white F2: 9 : 3 : 3 : 1 male female ¼ TC ¼ Tc ¼ tC ¼ tc ¼ TC ¼ Tc ¼ tC ¼ tc  TTCC  TTcC  tTCC  tTcC  TTCc  TTcc  tTCc  tTcc  TtCC  TtcC  ttCC  ttcC  TtCc  Ttcc

9. Tall colored x Dwarf white P TtCc ttcc G ¼TC ¼Tc ¼tC ¼tc tc ¼TtCc ¼Ttcc ¼ttCc ¼ttcc Tall colored Tall white Dwarf colored Dwarf white

10. LAW OF INDEPENDENT ASSORTMENT vs. MEIOSIS

15. Dihybrid : 9/16 wild type phenotypes 3/16 wild type wings, ebony body 3/16 vestigial wings, wild type body 1/16 vestigial ebony F 2 : All wild type phenotypes, F 1 X F 1 F 1 : Homozygous wild type X Vestigial ebony P: