Digestion of Lipids and Poteins

• What are lipids hydrolysed by?

  Lipases.
• Where are lipases produced?


  In the pancreas.
• What bond does lipase hydrolse?

  The ester bond found in triglycerides.
• What is a monoglycerid?

  A glycerol molecule with a single fatty acid attached to it.
• What are lipids first split up into?


  Tiny droplets called micelles.
• What are lipids first split up by to produce micelles?


  Bile salts.
• What produces bile salts?

  The liver.
• What is emulsification?


  The process of lipids being split into tiny droplets called micelles by bile salts.
• What does emulsification do?


  Increases the surface area of the lipids so that the hydrolysis is speeded up.
• What are proteins hydrolysed by?

  A group of enzymes called peptidases.
• What are peptidases?


  Types of protease enzymes that break down peptide bonds.
• What do endopeptidases do?


  Hydrolyse the peptide bonds between amino acids in the central region of the protein to form peptide molecules.
• What do exopeptidases do?


  Hydrolyse the peptide bonds on the end amino acids of the peptide molecules formed by endopeptidases to release dipeptides and single amino acids.
• What do dipeptidases do?


  Hydrolyse the bond between the two amino acids of a dipeptide.
• Where are dipeptidases?

  Membrane-bound to the cell-surface membrane of the epithelial cells lining the ileum.