There are two general categories of lipids. Simple lipids such as steroids and prostaglandins are not able to be hydrolyzed into smaller subuntis. Complex lipids such as true fats, phospholipids, and waxes can be hydrolyzed. A fatty acid is a long-chain carbon skeleton that has a carboxylic acid functional group. Saturated fatty acid refers to carbon skeleton that has as much hydrogen bonded to it as possible.
Examples are butter, whale blubber, suet, lard , etc.
If the carbons are double-bonded to each other at one or more points, the fatty acid is said to be unsaturated . Examples are peanut oil, corn oil, olive oil, etc. When glycerol and 3 fatty acid chains are combined, a triglyceride or fat molecule is formed. Fats are important molecules for storing energy. There is twice as much energy in a gram of fat as in a gram of sugar.