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MeiosisMeiosis
MeiosisMeiosisA type of cell division that
produces four cells each with half the number of chromosomes as the parents
Homologous Chromosomes: Two pairs of chromosomes that carry the same genetic material
Haploid and DiploidHaploid and Diploid
Haploid◦A cell with a single set of chromosomes
◦Shown as n◦A human has 23 chromosomes
Diploid◦A cell with two sets of chromosomes
◦Shown as 2n◦A human has 46 chromosomes
as 2n
MeiosisMeiosis
Produces 4 genetically different haploid cells
Has two division stages◦Meiosis I◦Meiosis II
MeiosisMeiosis
Meiosis IMeiosis IProphase I
◦Creation of homologous chromosomes
◦Tetrads are formed◦Homologous chromosomes crossover
Meiosis IMeiosis IMetaphase I
◦Tetrads line upAnaphase I
◦Homologous chromosomes separate
Telophase I and Cytokinesis◦Cells separate with
homologous chromosomes
Meiosis IMeiosis I
Meiosis IIMeiosis IIProphase IIMetaphase II
◦Sister Chromatids Line upAnaphase II
◦Sister Chromatids separate Telophase II and Cytokinesis
◦Cells split and create haploid genetically different daughter cells
MeiosisMeiosisCreates four genetically different daughter cells
Crossing over creates genetic variation
Only sex cells go through meiosis
Gamete: A sex cell created by meiosis- Sperm or Egg
Mitosis VS. Mitosis VS. MeiosisMeiosisMitosis
◦Creates 2 identical daughter cells
◦Does not exchange or change genetics
◦One stage◦Diploid
Meiosis◦Creates 4 genetically different daughter cells
◦Exchanges or changes genetics through crossing over
◦Two stages◦Haploid