FATS

Basically, fats are composed of twp parts, glycerol and fatty acids, and three fatty acids are joined with one glycerol molecule by ester link, forming triacylglycerol. saturated and unsaturated fatty acid is also an important fact, one difference between them is that saturated fatty acid has no double bonds, while unsaturated  fatty acid has one or more double bonds. they also vary in shapes of molecules, unsaturated fat has a bend shape, while saturated fat is a straight shape. And we also talked about phospholipids, which two fatty acids and one phosphate are attached to one glycerol molecule, and it is the major component of the cell membranes.