• Bile is an?alkaline?substance produced by cells in the?liver
• Before being released into the?small intestine?bile is stored in the?gallbladder

Bile production and secretion

• Bile has two main roles: 

   

  1. Neutralising?the?hydrochloric acid?from the stomach
     • The?alkaline?properties of bile allow for this to occur
     • This neutralisation is essential as enzymes in the small intestine have a higher (more alkaline) optimum pH than those in the stomach

      

  2. Breaking apart large drops of fat into smaller ones?(and so increasing their surface area)
     • This is known as?emulsification

      

   

• The more?alkaline conditions?and?larger surface area?allows lipase to?chemically?break down the fat (lipids) molecules into?glycerol?and?fatty acids?at a faster rate

Bile salts break large lipid droplets into smaller ones with a larger surface area