any of the microscopic rod-shaped bodies formed by the incorporation of the chromatin in a cell nucleus during mitosis and meiosis: they carry the genes that convey hereditary characteristics, and are constant in number for each species
A threadlike linear strand of DNA and associated proteins in the nucleus of eukaryotic cells that carries the genes and functions in the transmission of hereditary information.
A circular strand of DNA in bacteria that contains the hereditary information necessary for cell life.