LIFE 102 Lecture Notes - Sister Chromatids, Mendelian Inheritance, Genetic Variation
Document Summary
Concept 13. 3: meiosis reduces the number of chromosome sets from diploid to haploid. Like mitosis, meiosis is preceded by the replication of chromosomes. Meiosis takes place in two sets of cell divisions, called meiosis i and meiosis ii. The two cell divisions result in four daughter cells, rather than the two daughter cells in mitosis. Each daughter cell has only half as many chromosomes as the parent cell. In the first cell division (meiosis i), homologous chromosomes separate. Meiosis i results in two haploid daughter cells with replicated chromosomes; it is called the reductional division. In the second cell division (meiosis ii), sister chromatids separate. Meiosis ii results in four haploid daughter cells with unreplicated chromosomes; it is called the equational division. Meiosis i is preceded by interphase, in which chromosomes are replicated to form sister chromatids. The sister chromatids are genetically identical and joined at the centromere.
