This key facts covers Key Facts About the Digestive System within The Human Digestive System for GCSE Biology. Structure and function of digestive organs, mechanical and chemical digestion, enzymes, absorption, and practical investigations It is section 7 of 15 in this topic. Use this key facts to connect the idea to the wider topic before moving on to questions and flashcards.
Key Facts About the Digestive System
- Length: The alimentary canal is approximately 9 meters (30 feet) long
- Surface Area: The small intestine has a surface area of about 200 square meters due to villi
- Transit Time: Food takes 24-72 hours to complete the journey through your system
- Stomach Acid: pH between 1.5-3.5, strong enough to dissolve metal
- Peristalsis: Wave-like muscle contractions move food throughout the system
- Daily Production: Your body produces 1.5 liters of saliva and 2.5 liters of gastric juice daily
Practice questions for The Human Digestive System
Which organ produces hydrochloric acid to kill bacteria in food?
Explain the role of bile in the digestive system.
Quick recall flashcards
What are villi?
Villi are tiny finger-like projections on the wall of the small intestine that greatly increase the surface area for absorption of nutrients.
What is peristalsis?
Peristalsis is the wave-like contractions of smooth muscle that push food through the digestive system. Circular muscles contract behind food while longitudinal muscles relax in front.