10/21 bio notes
90% of time spent on prophase. Synapsis (process) put together homologous c somes. DONT DAY SISTER CHROMATIDS IN MEIOSIS I. Homologous c somes (similar in size and shape) synapsis brings homologous chromosomes together. They also cross over while they are together. DNA mixes up.How do you get variety in meiosis? (Synapsis)..
Chiasmata holds the tetras together, gotta do with the switching up. Tetra: 4 (4 chromatids)
In Metaphase I: the tetrads line up. Random assortment (the tetrads don’t care how they line up, they want variety). In anaphase the tetrads are pulled apart. In telophase I: 2 cells, those cells are haploid (DNA mixed up).
Meiosis II: questions: in meiosis two — there are no such things as tetrads, you call it sister chromatids. Do you recognize there are no such things as tetrads?
Diploid 2n. Human diploid 46
Haploid n: human 23.