Some common types of lipids that you are probably familiar with are fat, oils, and waxes. Like carbohydrates, lipids are organic molecules. However, lipids have a more complex structure than carbohydrates and are larger molecules.
Lipids include several different types of groups. The first is triglycerides. Stated somewhat simply, triglycerides consist of a glycerol molecule that is bound to three long-chain fatty acids.
Glycerol is a polyalcohol and fatty acids are long-chain carboxylic acid. Triglycerides are the most common lipids and make up fats and oils. A second grouping is phospholipids.
These consist of two fatty acids bound to a phosphate head group. The fatty acid portions avoid water, meaning they’re hydrophobic, while the phosphate head groups seek water, meaning their hydrophilic.
Phospholipids have a structural function. They make up a cell and organelle membranes in your body. A third group is steroids, which are lipids that are derived from cholesterol. Steroids have a four-ring structure with a hydroxyl group at one end and a short carbon chain at the opposite end.
Cholesterol is also found in cell membranes and circulates in the blood. Another type of steroids are hormones. Now, the fourth group of lipids that we’re going to talk about are waxes, which are formed when a long-chain alcohol binds to a long-chain fatty acid.
Again, some common types of lipids are fats, oils, and waxes, and like cholesterol, lipids are organic molecules.