What are nucleosomes?
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Interested in DNA packaging?
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The average size of a chromosome is 5 micrometers, but the length of the DNA molecule inside it, is about 5 cm long. How are 5 cm of a double stranded DNA helix compacted into a 5 cm long chromosome? The answers is amazing: nucleosomes and supercoiling of chromatin fibers!
Nucleosomes also play a role in DNA expression.
Only about 1.5% of the human DNA contains genes.
Introns are examples of non-coding DNA with no defined function.
DNA promoter are examples of non-coding DNA with a function.