====== Chromosome ====== Chromosomes are long, thread-like structures within the nucleus of human cells that contain [[genetic information]] in the form of [[DNA]]. Each chromosome has a long arm (referred to as the q arm) and a short arm (referred to as the p arm), which are separated by a central region called the centromere. A chromosome is packaged and organized [[chromatin]], a complex of macromolecules found in cells, consisting of [[DNA]], protein, and [[RNA]]. The main information-carrying macromolecule is a single piece of coiled double-stranded DNA, containing many [[gene]]s, regulatory elements, and other non-coding DNA. The DNA-bound macromolecules are proteins, which serve to package the DNA and control its functions. Chromosomes vary widely between different organisms. Some species also contain plasmids or other extrachromosomal DNA. ---- There are two types of chromosomes: autosomes and sex chromosomes. The sex chromosomes (X and Y) determine an individual's biological sex, while autosomes contain genes responsible for various traits and characteristics unrelated to sex determination. ---- [[Chromosome 1]] [[Chromosome 2]] [[Chromosome 3]] [[Chromosome 14]] [[Chromosome 21]]