Help store energy and provide structural support. Fatty acids consist of a hydrocarbon chain and an attached carboxylic acid group. They are a building block of more complex lipids. Sterol lipids are cholesterol and others like it. They are a very important part of membrane lipids. Sterols also act as hormones and signaling molecules. Fats are triglycerides, glycerol and three fatty acids. They come in two forms, saturated and unsaturated. Saturated fats have hydrogen molecules in all available places. Unsaturated fats are made up differently, bond-wise, so they don't have many places for hydrogen to connect. Pancreatic lipase breaks down fat bonds and releases fatty acids. Triglycerides cannot be absorbed by the duodenum, but its smaller forms can, such as monoglycerides and fatty acids. Then you need to break them down into fatty acids and other compounds to use