Revision Notes

• What is the definition of digestion?


  Digestion is the process by which your body breaks down food into smaller components that can be absorbed into the bloodstream.
• What is the main purpose of digestion?


  The main purpose of digestion is to extract nutrients, provide energy, and support growth and cell repair.
• What are the primary purposes of digestion?


  - Extract nutrients from food - Provide energy for bodily functions - Support growth and cell repair
• What are the main organs involved in digestion?


  The main organs involved in digestion are the mouth, esophagus, stomach, small intestine, large intestine, liver, pancreas, and gallbladder.
• What role does the mouth play in digestion?


  The mouth is where digestion begins with chewing and saliva.
• What is the function of the esophagus in the digestive system?


  The esophagus is the tube that moves food from the mouth to the stomach.
• What happens in the stomach during digestion?


  The stomach mixes food with digestive juices.
• Where does most digestion and nutrient absorption occur?


  Most digestion and nutrient absorption occurs in the small intestine.
• What is the role of the large intestine in digestion?


  The large intestine absorbs water and forms stool.
• What does the liver do in the digestive process?


  The liver produces bile to help break down fats.
• What is the function of the pancreas in digestion?


  The pancreas produces enzymes for digestion.
• What does the gallbladder do in the digestive system?


  The gallbladder stores and releases bile.
• What is mechanical digestion?


  Mechanical digestion is the physical breakdown of food into smaller pieces.
• What are the parts of the digestive system where mechanical digestion occurs?


  Mechanical digestion occurs in the mouth, stomach, small intestine, and large intestine.
• What is the purpose of mechanical digestion?


  The purpose of mechanical digestion is to increase the surface area of food particles for easier enzyme action during chemical digestion.
• What are the forms of mechanical digestion?


  Forms of mechanical digestion include chewing, churning, and peristalsis.
• What is chemical digestion?


  Chemical digestion involves breaking down food molecules into smaller, absorbable units using enzymes and other chemicals.
• What happens in the mouth during chemical digestion?


  Salivary amylase begins breaking down carbohydrates in the mouth.
• What role does hydrochloric acid play in the stomach?


  Hydrochloric acid activates pepsin, which starts protein digestion.
• What is the role of bile in digestion?


  Bile emulsifies fats in the small intestine, making them easier for lipase to break down.
• What is absorption in the digestive process?


  Absorption occurs mainly in the small intestine, where nutrients pass through the intestinal wall into the bloodstream or lymphatic system.
• What is elimination in the digestive process?


  Elimination occurs in the large intestine, where water is absorbed from indigestible food matter and remaining waste forms stool.
• How is waste eliminated from the body?


  Waste is eliminated through the rectum and anus.
• What is the role of bacteria in the large intestine?


  Bacteria in the colon break down some remaining nutrients.
• What happens to water in the large intestine?


  Water is absorbed from indigestible food matter in the large intestine.
• What is the final product of the elimination process?


  The final product of the elimination process is stool.
• What is the role of the rectum in elimination?


  The rectum stores waste before it is eliminated from the body.
• What is the role of the anus in elimination?


  The anus is the opening through which waste is expelled from the body.