Digestive System: Enzymes and Absorption

📋 Course Outline

1. Hydrochloric acid and pepsin activity
2. Enzymes, digestion types, and digestive system organs
3. Bile, fat emulsification, and duodenum neutralisation
4. Small intestine absorption and villi microvilli

📖 1. Hydrochloric acid and pepsin activity

🔑 Key Concepts & Definitions

• Hydrochloric acid : Hydrochloric acid is a gastric juice component that creates a very low pH in the stomach.
• Pepsin activity : Pepsin activity is the effectiveness of the enzyme pepsin, which depends on the surrounding pH.

📝 Essential Points

• Hydrochloric acid provides a low pH that denatures enzymes in harmful microorganisms from food.
• Hydrochloric acid helps set the optimum pH needed for pepsin to work effectively.
• Pepsin works best only when the stomach environment reaches its optimum pH range.

💡 Memory Hook

Low pH = “kill + prime”: denature microbes and prime pepsin.

📖 2. Enzymes, digestion types, and digestive system organs

🔑 Key Concepts & Definitions