DNA, Carrier of Genetic Information

A Molecule Present in Every Cell

Every cell in your body, from neurons to skin cells, contains the same molecule in its nucleus: DNA, or deoxyribonucleic acid. It carries, in coded form, all the information needed to build and run a living organism.

Information Passed Down from Generation to Generation

DNA is not just a working molecule: it is also the carrier of heredity. During reproduction, each parent passes a copy of their DNA to their offspring, which explains the resemblance between parents and children, in humans as in other species.

Where Is DNA Found?

In organisms whose cells have a nucleus (eukaryotic cells), DNA is stored in the nucleus, in the form of chromosomes. In bacteria, which lack a nucleus, DNA floats directly in the cytoplasm.

The Same Molecule, Different Information

An essential point to understand: the DNA molecule has the same chemical structure in all living things — bacteria, oak trees, or humans. What changes from one species to another, and from one individual to another, is not the chemical nature of DNA, but the order in which its elements are linked together. It is this order, a true sequence of chemical "letters", that encodes the information.

Key Takeaway

DNA is the universal molecule of life: present in every species, it stores the information that directs the construction and functioning of the organism, and is passed down from one generation to the next.