* Organic molecules contain carbon: DNA is made up of long chains of nucleotides, which themselves are composed of carbon, hydrogen, oxygen, nitrogen, and phosphorus. The presence of carbon is a defining characteristic of organic molecules.

* Organic molecules are typically associated with living things: DNA is the blueprint of life, carrying the genetic instructions for an organism. It's a fundamental component of all living cells.

* Organic molecules have complex structures: DNA's double helix structure is a complex arrangement of organic molecules, showcasing the intricate nature of organic compounds.

In contrast, inorganic molecules generally lack carbon and are often found in non-living materials. Examples include water (H₂O), salt (NaCl), and minerals.