Homologt

Homologt is a term that appears in several languages as the cognate of the English "homologous" or "homology." In biology, it denotes similarity arising from shared ancestry rather than from convergent evolution. In English, the standard forms are "homologous" (adjective) and "homology" or "homolog" (noun).

In genetics and cytogenetics, homologous chromosomes are a pair of chromosomes in a diploid cell that carry the same genes in the same order, one inherited from each parent. During meiosis, homologous chromosomes pair and may exchange genetic material through crossing over, producing recombinant chromatids while retaining gene correspondence across the pair.

In molecular biology and comparative genomics, "homologous" describes genes or proteins that descend from a common ancestral sequence. Such genes are called homologs; when found in different species, they are orthologs, whereas duplicates within a species are paralogs. Homology underpins conservation of structure and often of function, though not always.

The term is distinct from analogy, where similarity arises from convergent evolution rather than shared ancestry. In Swedish and some other languages, "homologt" is used to translate "homologous," but in English the usual term is "homologous."