Lipids are better known as fats, but what are they specifically? (Select one that doesn't apply.)

Fatty acids are the building blocks of many lipids, including triglycerides and phospholipids. They consist of long hydrocarbon chains and can be saturated or unsaturated, playing crucial roles in energy storage and cellular structure. As essential components of lipid molecules, fatty acids are inherently classified as lipids.

Phospholipids are a major class of lipids composed of two fatty acids, a glycerol backbone, and a phosphate group. They are integral to forming cell membranes, providing a bilayer structure that is fundamental for cellular integrity and function. As a key type of lipid, phospholipids are vital for biological membranes.

Steroids are a category of lipids characterized by a carbon skeleton with four fused rings. They play important roles in cellular signaling and structural functions in membranes. As a well-defined class of lipids, steroids are integral to various biological processes, including hormone production and regulation.