Which of the following elements is primarily associated with the structure of fatty acids found in the plasma membrane?

Fatty acids, which are key components of phospholipids that make up cell membranes, primarily consist of long hydrocarbon chains. The defining structure of a fatty acid includes a carboxyl group (-COOH) at one end and a long chain of carbon atoms that can vary in length and saturation.

The predominant element in these hydrocarbon chains is carbon, as each carbon atom in the chain can bond with hydrogen atoms, forming the backbone of the fatty acid. The presence of carbon in fatty acids allows them to vary in terms of the number of double bonds (unsaturation) and the length of the alkyl chain, which can greatly affect the physical and chemical properties of the resulting lipid in the membrane.

In addition to carbon, fatty acids incorporate hydrogen and oxygen (from the carboxyl group), but when considering the basic structural backbone and the predominant atom in fatty acids, carbon is the most significant. Therefore, recognizing the critical role of carbon in the structure of fatty acids helps clarify its essential function in the overall architecture of the plasma membrane.