Digestion and absorption

• What is the main topic of this section?

  More Exchange and Transport Systems
• What are the main processes involved in digestion and absorption?

  • Digestion of carbohydrates
  • Digestion of lipids
  • Digestion of proteins
  • Absorption of digestion products
• What are digestive enzymes responsible for?

  Breaking down food into absorbable units
• How do lipases function in lipid digestion?

  They hydrolyze triglycerides into fatty acids
• What role do bile salts play in lipid digestion?

  They emulsify lipids to form micelles
• Why are micelles important in lipid digestion?

  They increase the surface area for lipase action
• What is the function of pepsin in protein digestion?

  It hydrolyzes peptide bonds in proteins
• What conditions are necessary for pepsin to function?

  It requires an acidic environment
• What do exopeptidases do during protein digestion?

  They hydrolyze peptide bonds at protein ends
• What are dipeptidases specifically responsible for?

  Hydrolyzing dipeptides into amino acids
• Where are dipeptidases located in the body?

  In the cell membrane of intestinal epithelial cells
• What are the key steps in the absorption of digestion products?

  1. Hydrolysis of macromolecules
  2. Formation of micelles
  3. Transport across epithelial cells
  4. Entry into the bloodstream
• What is a hydrolysis reaction?

  A reaction that breaks bonds using water
• What is the action of exopeptidases in protein digestion?

  They remove single amino acids from proteins
• What type of enzymes are needed to break down lipids?

  Lipases
• How are micelles formed during digestion?

  Bile salts emulsify lipids into small droplets
• How are monoglycerides and fatty acids absorbed across the ileum epithelium?

  Through diffusion and transport proteins
• How do sodium ions assist in the transport of amino acids?

  They create a gradient for co-transport
• What is the role of sucrase in the body?

  It hydrolyzes sucrose into glucose and fructose
• What do Figures 5 and 6 illustrate in digestion?

  • Figure 5: Emulsification of lipids by bile salts
  • Figure 6: Hydrolysis of triglycerides by lipases
• What is the significance of monitoring the contents during digestion?

  To ensure proper nutrient absorption and digestion