Stack, Stephen M. Department of Biology, Colorado State University, Fort Collins, Colorado.
Anderson, Lorinda K. Department of Biology, Colorado State University, Fort Collins, Colorado.
Last reviewed:September 2016
Show previous versions
- Interphase chromosomes
- Structure and composition of mitotic chromosomes
- Euchromatin and heterochromatin
- Chromosome sets, genomes, ploidy, and homologs
- Karyotypes and idiograms
- Techniques for spreading and staining chromosomes
- Special chromosomes
- Related Primary Literature
- Additional Reading
A DNA–protein complex in the nucleus of eukaryotic cells. Chromosomes are linear (usually) or circular structures containing deoxyribonucleic acid (DNA) complexed with histone and nonhistone proteins, a centromere, and a telomere at each end, if linear. These threadlike, tightly packed structures are seen in animals, plants, and other eukaryotes during mitotic and meiotic cell divisions (Fig. 1). The single DNA molecule in each chromosome carries a unique complement of linearly arranged genes. Chromosomes were so named because, after staining, nineteenth-century light microscopists saw chromosomes as colored bodies in cells. The combination of DNA and proteins in chromosomes is called chromatin. Collectively, the DNA from all the chromosomes in a nucleus is the hereditary blueprint for the species. Eukaryotes (plants, animals, fungi, and protists) usually have one nucleus in each cell. A nucleus is a double membrane-bound compartment in which chromosomes are located in interphase between cell divisions. In contrast, prokaryotes, such as bacteria and their allies [including mitochondria and chloroplasts (cell plastids)], do not have true chromosomes or nuclei because prokaryotes do not confine their small, single circle of DNA in a membrane-bound compartment. See also: Cell division; Deoxyribonucleic acid (DNA); Eukaryotae; Gene; Histone; Meiosis; Mitosis; Protein
The content above is only an excerpt.
for your institution. Subscribe
To learn more about subscribing to AccessScience, or to request a no-risk trial of this award-winning scientific reference for your institution, fill in your information and a member of our Sales Team will contact you as soon as possible.
to your librarian. Recommend
Let your librarian know about the award-winning gateway to the most trustworthy and accurate scientific information.
AccessScience provides the most accurate and trustworthy scientific information available.
Recognized as an award-winning gateway to scientific knowledge, AccessScience is an amazing online resource that contains high-quality reference material written specifically for students. Contributors include more than 9000 highly qualified scientists and 43 Nobel Prize winners.
MORE THAN 8700 articles covering all major scientific disciplines and encompassing the McGraw-Hill Encyclopedia of Science & Technology and McGraw-Hill Yearbook of Science & Technology
115,000-PLUS definitions from the McGraw-Hill Dictionary of Scientific and Technical Terms
3000 biographies of notable scientific figures
MORE THAN 19,000 downloadable images and animations illustrating key topics
ENGAGING VIDEOS highlighting the life and work of award-winning scientists
SUGGESTIONS FOR FURTHER STUDY and additional readings to guide students to deeper understanding and research
LINKS TO CITABLE LITERATURE help students expand their knowledge using primary sources of information