Organic molecules are primarily made up of two essential elements: carbon and hydrogen. These elements are fundamental to the structure of organic compounds, which also include other elements such as oxygen, nitrogen, sulfur, and phosphorus. However, the presence of carbon and hydrogen is what distinctly characterizes organic molecules.
Carbon is unique in its ability to form four covalent bonds with other atoms, allowing for a vast diversity of structures, including chains and rings. This property enables the formation of complex organic compounds, such as carbohydrates, proteins, lipids, and nucleic acids, which are crucial for life.
Hydrogen, on the other hand, bonds easily with carbon, completing its tetravalent nature and contributing to the stability and functionality of the molecules. The combination of carbon and hydrogen not only establishes the backbone of organic compounds but also influences their reactivity and interactions in biological systems.