Lipids Lipids are diverse hydrophobic molecules. They are composed of fats and glycerol. The fats store large amounts of energy. Fats, also known as triacylglycerols, are constructed by joining a glycerol molecule, and three fatty acid by dehydration reactions.
Phospholipids are major components of the cell membrane.
They have hydrophobic tails, and hydrophilic heads. Steroids include cholesterol and certain hormones. Steroids have a basic structure of four fused rings of carbon atoms.