Describe the process by which lipids are 'broken down' by the digestive system, and how bile facilitates this process.

Lipids are broken down by lipases into glycerol and fatty acids.
Bile, made in the liver and stored in the gall bladder, facilitates this process by emulsifying fats into smaller droplets. This increases the amount of surface area available to lipases, consequently meaning that a larger number of lipid molecules can be broken down at one time by the lipases.In addition to this increase in available surface area, the alkaline conditions provided by the bile also speeds up the action of lipase.