organelle organization chromosome organization GO:0007001 A process that is carried out at the cellular level that results in the assembly, arrangement of constituent parts, or disassembly of chromosomes, structures composed of a very long molecule of DNA and associated proteins that carries hereditary information. This term covers covalent modifications at the molecular level as well as spatial relationships among the major components of a chromosome. nuclear genome maintenance GO:0051277 GO:0051276 maintenance of genome integrity chromosome organisation chromosome organization and biogenesis biological_process