The repair of single strand breaks in DNA. Repair of such breaks is mediated by the same enzyme systems as are used in base excision repair [goid 12] [pmid 12743712] [evidence IDA]; The controlled breakdown of nucleosomes, the beadlike structural units of eukaryotic chromatin composed of histones and DNA [goid 6337] [pmid 10781074] [evidence IMP]; Dynamic structural changes to eukaryotic chromatin occurring throughout the cell division cycle. These changes range from the local changes necessary for transcriptional regulation to global changes necessary for chromosome segregation [goid 6338] [pmid 12743712] [evidence IDA]; Repression of transcription by altering the structure of chromatin, e.g. by conversion of large regions of DNA into an inaccessible state often called heterochromatin [goid 6342] [pmid 11315969] [evidence IEP]; The biological process whose specific outcome is the progression of a multicellular organism over time from an initial condition (e.g. a zygote or a young adult) to a later condition (e.g. a multicellular animal or an aged adult) [goid 7275] [evidence IEA]; The process of formation of spermatozoa, including spermatocytogenesis and spermiogenesis [goid 7283] [evidence IEA]; The change in shape of the spermatid nucleus from a spherical structure to an elongated organelle, during the latter part of spermatid differentiation [goid 7290] [pmid 10781074] [evidence IMP]; The regular alternation, in the life cycle of haplontic, diplontic and diplohaplontic organisms, of meiosis and fertilization which provides for the production offspring. In diplontic organisms there is a life cycle in which the products of meiosis behave directly as gametes, fusing to form a zygote from which the diploid, or sexually reproductive polyploid, adult organism will develop. In diplohaplontic organisms a haploid phase (gametophyte) exists in the life cycle between meiosis and fertilization (e.g. higher plants, many algae and Fungi); the products of meiosis are spores that develop as haploid individuals from which haploid gametes develop to form a diploid zygote; diplohaplontic organisms show an alternation of haploid and diploid generations. In haplontic organisms meiosis occurs in the zygote, giving rise to four haploid cells (e.g. many algae and protozoa), only the zygote is diploid and this may form a resistant spore, tiding organisms over hard times [goid 19953] [pmid 10781074] [evidence IMP]; The process whereby relatively unspecialized cells, e.g. embryonic or regenerative cells, acquire specialized structural and/or functional features that characterize the cells, tissues, or organs of the mature organism or some other relatively stable phase of the organism's life history. Differentiation includes the processes involved in commitment of a cell to a specific fate [goid 30154] [evidence IEA]; Any process involved in the controlled movement of a sperm cell [goid 30317] [pmid 10781074] [evidence IMP]; Replacement of sperm-specific chromosomal proteins with somatic histones, to allow the paternal genome to acquire a nucleosomal chromatin organization compatible with nuclear activity [goid 35042] [pmid 12743712] [evidence TAS]