When the information is needed, the DNA spiral unwraps itself temporarily so that the information that is needed can be copied. Chemical messengers then carry the information from the nucleus to the part of the cell where proteins are constructed from amino acids present in the cell. The chemical DNA letters A,C, G and T combine in a number of ways to make three letter words. Each three-letter word codes for a particular amino acid and directs the cell to insert that particular amino acid into the protein chain . Some proteins are simple chains of a few amino acids, while other proteins are more complex structures, made up of several amino acid chains .
Every person has a unique set of genes which are inherited from their parents.
Genes determine physical characteristics like eye and hair color, height and the shape of facial features. Many other traits such as personality, temperament, talents and mannerisms can also be influenced by genes. Some traits may resemble one parent and other may be a blend of both. Genes for some characteristics are stronger or more likely to appear in offspring than others. Each of the thousands of gene pairs in the body work as a team.