Essential Idea:
Meiosis leads to independent assortment of chromosomes
and unique composition of alleles in daughter cells
Understandings:
- Chromosomes replicate in interphase before meiosis
- Homologous chromosomes separate in meiosis I
- Sister chromatids separate in meiosis II
- Independent assortment of genes is due to the random orientation of pairs of homologous chromosomes in meiosis I
- Chiasmata formation between non-sister chromatids can result in an exchange of alleles
- Crossing over is the exchange of DNA material between non-sister homologous chromatids
- Crossing over produces new combinations of alleles on the chromosomes of the haploid cells
Skills:
- Drawing diagrams to show chiasmata formed by crossing over