Each set has 23 single chromosomes - 22 autosomes and an X or Y sex chromosome . Then mRNA travels out of the nucleus into the cytoplasm, to cell organelles called ribosomes. There, mRNA directs the assembly of amino acids that fold into completed protein molecule. Each human cell contains 23 pairs of chromosomes, which can be distinguished by size and by unique banding patterns. This set is from a male, since it contains a Y chromosome.
Females have two X chromosomes.
Different genes are activated in different cells, creating the specific proteins that give a particular cell type its character.