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Which organic molecules in living things contain carbon?

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A labeled diagram of the periodic table entry for carbon, showing its atomic number 6, symbol C, electron configuration, atomic weight range, solid physical state, hexagonal crystal structure, and weakly acidic oxide properties. Color coding and icons indicate it is a nonmetal, solid at room temperature, with hexagonal structure and weak acidity. — carbon Carbon and its properties.

Carbon is the fundamental structural element of all living things, forming the basis of the complex organic molecules that constitute cells. These molecules are primarily built from four major families of organic compounds:123

Carbohydrates: These are essential energy sources and structural components, often represented by the general formula $C_{x} (H_{2} O)_{y}$ . They include simple sugars and complex polysaccharides like starch and glycogen.431
Proteins: Composed of chains of amino acids, proteins serve as major structural elements, transporters, and enzymes that catalyze biological reactions.13
Nucleic Acids: DNA and RNA are composed of nucleotides and are responsible for storing and transmitting genetic information.13
Lipids: These molecules, which include fatty acids, function as stored energy and form the membranes that compartmentalize cells.13

Beyond these families, carbon is also a key component in vital substances such as hemoglobin, chlorophyll, hormones, and vitamins.5