- The repeating structural units of chromatin, each consisting of approximately 200 base pairs of DNA wound around a protein core. This core is composed of the histones H2A, H2B, H3, and H4.
Definition from: MeSH via Unified Medical Language System at the National Library of Medicine
- Any of the repeating globular subunits of chromatin that consist of a complex of DNA and histone and are thought to be present only during interphase.
Definition from: Merriam-Webster's Medical Dictionary by Merriam-Webster Inc.
- A nucleosome is the basic repeating unit of eukaryotic chromatin. In a human cell, about six feet of DNA must be packaged into a nucleus with a diameter less than a human hair. A single nucleosome consists of about 150 base pairs of DNA sequence wrapped around a core of histone proteins. The nucleosomes are arranged like beads on a string. They are repeatedly folded in on themselves to form a chromosome.
Definition from: Talking Glossary of Genetic Terms from the National Human Genome Research Institute
See also Understanding Medical Terminology.