Polyteny is a biological term that refers to the process of DNA replication, in which chromosomes undergo multiple rounds of replication without undergoing cell division. This leads to the formation of giant polytene chromosomes, which can be observed under a microscope. Synonyms for polyteny include endomitosis, endoreduplication, and polyploidy. Endomitosis occurs when mitosis is aborted, resulting in chromosomes that continue to replicate but remain in a single nucleus. Endoreduplication is a form of polyploidy, which occurs when the entire genome is duplicated within a single nucleus. Polyploidy can also occur through hybridization of two different species. These synonyms all describe the same process of DNA replication, resulting in larger chromosomes than normal.