483 Lecture Notes - Lecture 2: Sister Chromatids, Mitosis, Centromere
Document Summary
Cell reproduction (cell division) produces genetically identical daughter cells. Some organisms use mitosis to reproduce (asexual reproduction). It results in o spring that are genetically identical to the parent and to each other). Mitosis also enables multicellular organisms to grow and develop and to replace damage cells. Organisms that reproduce sexually carry out meiosis (a type of cell division that yields gametes with only half as many chromosomes as body cells). The genes of a eukaryotic genome are grouped into multiple chromosomes in the nucleus. Each chromosome contains one very long dna molecule, with many genes, that is wrapped around histone proteins. Individual chromosomes are coiled up and therefore visible with a light microscope only when the cell is in the process of dividing; otherwise, they are in the form of thin, loosely packed chromatin bers. Chromosomes contain the information needed to control cellular processes, therefore they must be copied and distributed to daughter cells.