Meiosis lecture for CHS IB Biology HL Year 1

1. Meiotic Cell Division

7. Periods of Prophase I A physical exchange of chromosome pieces A tetrad

8. Stages of Meiosis I Spindle apparatus complete; pairs of chromatids attached to kinetochore microtubules

10. Stages of Meiosis I 3-50 Homologous chromosomes separate from each other The centromere remains between sister chromatids

12. Stages of Meiosis II 1 of each type of chromosome (n) in each daughter cell (gamete)

13. Separation of Alleles During Meiosis Prophase I Metaphase I Anaphase I Telophase I Meiosis II Haploid cells Heterozygous ( Yy ) cell from a plant with yellow seeds y y y y y y y Y Y Y Y Y Y Y

14. Separation of Alleles During Meiosis Meiosis I Meiosis II or 2 Ry : : Heterozygous diploid cell ( YyRr ) to undergo meiosis y y y y y y y y y Y Y Y Y Y Y Y Y Y R R R r r y r r R R Y R R R R y R r r r r Y r Y y R r R r r 2 rY 2 ry 2 RY