What is the primary composition of lipids?

Lipids are primarily composed of carbon and hydrogen atoms. This is due to the nature of their molecular structure, which consists of long hydrocarbon chains or ring structures that are hydrophobic (water-repelling). The high ratio of hydrogen to carbon in lipids contributes to their role as energy-rich macromolecules, as they provide more energy per gram compared to carbohydrates and proteins.

Lipids also include various functional groups that can introduce oxygen, such as in triglycerides and phospholipids, but the foundational structure relies heavily on the carbon and hydrogen backbone. This composition allows lipids to form critical biological structures, such as cell membranes, and to participate in energy storage and signaling processes within the body. Understanding this basic composition is essential when studying metabolism, cell biology, and various biochemical pathways involving lipids.