Transcription 1/15/2026, 9:02:28 PM

Notes

• Mitosis: Overview Mitosis starts with one cell and ends with two. It begins with a cell that has 2n chromosomes and results in two genetically identical daughter cells, each also with 2n chromosomes. The process involves the division of one cell into two, producing cells that are identical to the parent cell. Why do cells divide? • For reproduction (unicellular organisms) • For growth • For repair of damaged tissues • Chromatin and Chromosomes Chromatin is DNA wrapped around histone proteins. When it condenses, it forms a chromosome. Sister chromatids are identical copies of a chromosome, connected at a specific region called the centromere. The X-shaped chromosome is more specific, with the sister chromatids held together in the middle by the centromere. • Centrosome and Centriole The centrosome contains a pair of centrioles enclosed in a membrane. The centriole is a component of the cytoskeleton and plays a key role in cell division. • Centromere and Homologous Chromosomes The centromere is the waist of the sister chromatids, where they are narrowed and held together. Homologous chromosomes are pairs, one from the mother and one from the father, with similar func...