DIGESTION AND ABSORBTION MISS ESTRUCH

• What does digestion involve?

  Hydrolysis of large insoluble molecules
• What are the three main types of molecules involved in digestion?

  Carbohydrates, lipids, and proteins
• What are the two types of enzymes mentioned for carbohydrate digestion?

  Amylase and membrane-bound disaccharidases
• Where is amylase produced?

  In the pancreas and salivary glands
• Where does carbohydrate digestion begin?

  In the mouth
• What happens to starch during carbohydrate digestion?

  It is hydrolyzed into disaccharides
• What is the first part of the small intestine called?

  Duodenum
• What do membrane-bound disaccharidases do?

  Hydrolyze disaccharides into monosaccharides
• What are two examples of membrane-bound disaccharidases?

  Sucrose and lactase
• What do endopeptidases hydrolyze?

  Peptide bonds within the polymer chain
• What do exopeptidases hydrolyze?

  Peptide bonds at the ends of the polymer chain
• Where does protein digestion start?

  In the stomach
• What is the role of lipase in lipid digestion?

  Hydrolyze ester bonds in triglycerides
• Where is lipase produced?

  In the pancreas
• What do bile salts do during lipid digestion?

  Emulsify lipids into tiny droplets
• What is an emulsion in the context of lipid digestion?

  Small droplets of lipids coated by bile salts
• Why is a larger surface area advantageous for digestion?

  It allows faster hydrolysis by lipase
• What are micelles?

  Spheres made of fatty acids and monoglycerides
• How do micelles aid in absorption?

  Deliver fatty acids to epithelial cells
• What is the role of villi in the ileum?

  Increase surface area for absorption
• What is co-transport in the context of absorption?

  A type of active transport for nutrients
• What happens to fatty acids after entering epithelial cells?

  They are reformed into triglycerides
• What is a chylomicron?

  A triglyceride combined with a protein
• How are chylomicrons absorbed into the body?

  Through lacteals in the lymphatic system
• What is the final destination of lipids absorbed by the lymphatic system?

  They drain into the capillary system
• What are the key processes involved in digestion and absorption?

  • Digestion: Hydrolysis of large molecules
  • Absorption: Uptake of small molecules
  • Involves carbohydrates, lipids, and proteins
  • Enzymes: Amylase, lipase, proteases
  • Co-transport for monosaccharides and amino acids
  • Micelles aid in lipid absorption
• What are the differences between physical and chemical digestion?

  • Physical digestion: Emulsification by bile salts
  • Chemical digestion: Hydrolysis by enzymes
  • Physical increases surface area for enzymes
  • Chemical breaks down molecules into absorbable forms
• What is the significance of villi and microvilli in the ileum?

  • Villi: Increase surface area for absorption
  • Microvilli: Further increase surface area
  • Contain capillary networks for efficient nutrient transport
  • Short diffusion distance enhances absorption efficiency
• How do bile salts enhance lipid digestion?

  • Emulsify large lipid droplets into smaller ones
  • Increase surface area for lipase action
  • Facilitate faster hydrolysis of triglycerides
• What is the role of the endoplasmic reticulum in lipid absorption?

  • Reforms fatty acids into triglycerides
  • Packages triglycerides into chylomicrons
  • Prepares lipids for transport in the body
• What are the two types of transport across membranes discussed in the session?

  Active transport and co-transport
• What is the purpose of subscribing to the channel mentioned in the video?

  To receive updates on new biology content
• What is the first type of transport mentioned in the diagrams?

  Simple diffusion
• How does simple diffusion occur across a membrane?

  It occurs down the concentration gradient without a protein
• What is the second type of transport mentioned in the diagrams?

  Facilitated diffusion
• How does facilitated diffusion differ from simple diffusion?

  It occurs through a protein down the concentration gradient
• What is the third type of transport mentioned in the diagrams?

  Active transport
• What is the main characteristic of active transport?

  It moves substances against their concentration gradient
• What energy source is required for active transport?

  ATP
• What role do carrier proteins play in active transport?

  They facilitate the movement of substances across membranes