Basic Biology of DNA
DNA is the abbreviation for deoxyribonucleic acid, which is the genetic material present in the cells of all living organisms. DNA is the fundamental building block for an individual's entire genetic makeup. A person's DNA is the same in every cell (with a nucleus). The DNA in a person's blood is the same as the DNA in their skin cells, semen, and saliva.
DNA is comprised of four building blocks called bases. The building blocks are: Cytosine, Guanine, Thymine, Adenine. These are commonly referred to as C, G, T, A. It is the order (sequence) of these building blocks that determines each person's genetic characteristics.
DNA is contained in blood, semen, skin cells, tissue, organs, muscle, brain cells, bone, teeth, hair, saliva, mucus, perspiration, fingernails, urine, feces, etc.
- Visit DNA From the Beginning to learn about classical and molecular genetics through animations, graphics, audio files, biographies, and test cases. DNA From the Beginning is presented by the Cold Springs Harbor Laboratory.
- Search for 'DNA' related information on the National Institute of Health's Office of Science Education Web site.
- Browse the Talking Glossary of Terms hosted by the National Human Genome Research Institute, National Institutes of Health.
