Final answer:
A nucleosome is a "bead" on a string of unfolded chromatin where DNA is wrapped around histone proteins. Nucleosomes produce a 3-fold packing ratio of DNA. Nucleosomes are present in both mitotic and non-mitotic chromosomes.
Step-by-step explanation:
A nucleosome is a "bead" on a string of unfolded chromatin where DNA is wrapped around histone proteins to form structures called nucleosomes. The nucleosomes produce a 30-nm fiber, resulting in a 3-fold packing ratio of DNA. Nucleosomes are not found only in mitotic chromosomes; they are present in both mitotic and non-mitotic chromosomes. A nucleosome consists of DNA wrapped around 8 histone proteins, plus a short segment of linker DNA.