Fatty acid synthesis is the process by which cells create fatty acids, which are essential components of lipids. This process primarily occurs in the cytoplasm of cells, where acetyl-CoA serves as the building block. Enzymes like fatty acid synthase facilitate the stepwise addition of carbon units, resulting in the formation of long-chain fatty acids. The synthesis begins with the conversion of glucose into pyruvate, which is then transformed into acetyl-CoA. Through a series of reactions, NADPH provides the reducing power needed for the synthesis. Ultimately, these fatty acids can be used for energy storage or as structural components in cell membranes.