structure
Last reviewed 01/2018
Chromosomes are formed by an impressive degree of superstructure formation:
- the DNA double helix winds around histone proteins to form nucleosomes
- multiple nucleosomes associate with each other along the DNA chain to form a chromatin fibre
- the chromatin fibre folds upon itself perpendicularly to an acidic protein strand to from heterochromatin
- heterochromatin coils into a strand to from a chromosome
Further, the chromosome can divide longitudinally to form chromatids. Chromatids are initially joined by a centromere. Telomeres are found at the end of chromosomes.