Humans possess a total of 23 pairs of chromosomes in their cells. Out of these, 22 pairs are autosomal chromosomes, which are non-sex chromosomes and carry the bulk of genetic information ranging from hair color to metabolic enzymes. The autosomal chromosomes are numbered from 1 to 22 based on their size, with chromosome 1 being the largest and chromosome 22 being relatively smaller. The 23rd pair consists of the sex chromosomes, X and Y, which determine an individual's sex. Thus, in normal humans, there are 22 pairs of autosomal chromosomes.