Centromere: a locusplugin-autotooltip__default plugin-autotooltip_bigLocus (plural form: loci): a physical location of a gene; often used as a synonym for a gene. on a chromosomeplugin-autotooltip__default plugin-autotooltip_bigChromosome: a structure that organizes dsDNA in a cell through interactions with various DNA binding proteins. that marks where spindleplugin-autotooltip__default plugin-autotooltip_bigSpindle: a rope-like structure that forms during mitosis or meiosis and pulls chromosomes apart. fibers attach during mitosisplugin-autotooltip__default plugin-autotooltip_bigMitosis: a type of cell division that generates two genetically identical daughter cells. and meiosisplugin-autotooltip__default plugin-autotooltip_bigMeiosis: a process involving two sequential cell divisions that usually produces four gametes (reproductive cells such as sperm or eggs)..