The cell cycle process in which replicated homologous chromosomes are organized and then physically separated and apportioned to two sets during the mitotic cell cycle. Each replicated chromosome, composed of two sister chromatids, aligns at the cell equator, paired with its homologous partner. One homolog of each morphologic type goes into each of the resulting chromosome sets.

The cell cycle process in which sister chromatids are organized and then physically separated and randomly apportioned to two sets during the second division of the meiotic cell cycle.

The cell cycle process in which spindle microtubules become physically associated with the proteins making up the kinetochore complex as part of mitotic metaphase plate congression.

The cell cycle process in which centromere chromatin structure is compacted prior to and during mitosis.

The region of a chromosome that includes the centromeric DNA and associated proteins. In monocentric chromosomes, this region corresponds to a single area of the chromosome, whereas in holocentric chromosomes, it is evenly distributed along the chromosome.

A multisubunit complex that is located at the centromeric region of DNA and provides an attachment point for the spindle microtubules.

A multisubunit complex that is located at the centromeric region of a condensed nuclear chromosome and provides an attachment point for the spindle microtubules.

A membrane-bounded organelle of eukaryotic cells in which chromosomes are housed and replicated. In most cells, the nucleus contains all of the cell's chromosomes except the organellar chromosomes, and is the site of RNA synthesis and processing. In some species, or in specialized cell types, RNA metabolism or DNA replication may be absent.

A membrane-bounded organelle of eukaryotic cells in which chromosomes are housed and replicated. In most cells, the nucleus contains all of the cell's chromosomes except the organellar chromosomes, and is the site of RNA synthesis and processing. In some species, or in specialized cell types, RNA metabolism or DNA replication may be absent.

A small, dense body one or more of which are present in the nucleus of eukaryotic cells. It is rich in RNA and protein, is not bounded by a limiting membrane, and is not seen during mitosis. Its prime function is the transcription of the nucleolar DNA into 45S ribosomal-precursor RNA, the processing of this RNA into 5.8S, 18S, and 28S components of ribosomal RNA, and the association of these components with 5S RNA and proteins synthesized outside the nucleolus. This association results in the formation of ribonucleoprotein precursors; these pass into the cytoplasm and mature into the 40S and 60S subunits of the ribosome.

The part of the cytoplasm that does not contain organelles but which does contain other particulate matter, such as protein complexes.

A protein complex required for clamping microtubule binding sites, ensuring orientation of sister kinetochores to the same pole (mono-orientation) during meiosis I. In the yeast S. cerevisiae this complex consists of Csm1p, Lrs4p, Hrr25p and Mam1p; in S. pombe Psc1 and Mde4 have been identified as subunits.

The innermost portion of the centromeric region of a chromosome, encompassing the core region of a chromosome centromere and the proteins that bind to it.

A spindle that forms as part of mitosis. Mitotic and meiotic spindles contain distinctive complements of proteins associated with microtubules.