Chromosomes are made of DNA and proteins. Specifically, each chromosome consists of a long, continuous molecule of DNA that is tightly coiled and packaged around proteins called histones. These histones help support the chromosome's structure and allow the DNA to be compact enough to fit inside the cell nucleus
. This DNA-protein complex is known as chromatin. The DNA in chromosomes contains genes, which are sequences that code for proteins and determine genetic traits. The DNA wraps around histones forming nucleosomes, which further fold and condense to create the chromosome's compact structure visible during cell division
. In summary, chromosomes are composed primarily of:
- DNA: the genetic material carrying instructions for life
- Histone proteins: around which DNA is tightly coiled
- Other structural proteins that help organize and regulate DNA function
This packaging allows chromosomes to efficiently store and manage genetic information within the nucleus of cells
