1. Digestion
Topic 6.1
(modified for 2016 exam)

2. 6.1.1 Explain why digestion of large food molecules is essential.
Hydrolysis (water-splitting) is the reaction used to break down large
organic molecules (carbohydrates, lipids, and proteins). Enzymes are
needed for these reactions.

3. 6.1.2 Explain the need for enzymes in digestion.

4. 6.1.3 State the source, substrate, products and optimum pH conditions for one amylase, one protease and one lipase.

5. 6.1.4 Draw and label a diagram of the digestive system.

6. 6.1.4 Draw and label a diagram of the digestive system.

7. 6.1.5 Outline the function of the stomach, small intestine and large intestine.
Hydrochloric acid in the stomach lowers the pH to around 2,
killing bacteria and denaturing proteins.
Pepsin enzyme starts protein digestion.
Muscular actions aid mechanical digestion.
Stretch receptors in the muscular wall triggers release of
enzymes.

8. 6.1.5 Outline the function of the stomach, small intestine and large intestine.

9. 6.1.5 Outline the function of the stomach, small intestine and large intestine.

10. 6.1.6 Distinguish between absorption and assimilation.
Digestion breaks down large food molecules into smaller molecules.
Absorption is the uptake of these molecules into the blood.
Once in the blood, they are carried to the tissues where they are
assimilated – taken in to be used.

11. 6.1.7 Explain how the structure of the villus is related to its role in absorption and transport of the products of digestion.

12. 6.1.7 Explain how the structure of the villus is related to its role in absorption and transport of the products of digestion.

13. H2.1 State that digestive juices are secreted into the alimentary canal by glands, including salivary glands, gastric glands in the stomach wall, the pancreas and the wall of the small intestine.

14. H2.1 State that digestive juices are secreted into the alimentary canal by glands, including salivary glands, gastric glands in the stomach wall, the pancreas and the wall of the small intestine.
Salivary amylase
pepsin
Pancreatic amylase
Endopeptidases
Exopeptidases
carbohydrases
peptidases

15. H2.5 Outline the role of membrane-bound enzymes on the surface of epithelial cells in the small intestine in digestion.

16. H3.1 Draw and label a diagram showing a transverse section of the ileum as seen under a light microscope.

17. H3.3 Explain the mechanisms used by the ileum to absorb and transport food, including facilitated diffusion, active transport, and endocytosis.

18. H3.3 Explain the mechanisms used by the ileum to absorb and transport food, including facilitated diffusion, active transport, and endocytosis.

19. H3.3 Explain the mechanisms used by the ileum to absorb and transport food, including facilitated diffusion, active transport, and endocytosis.

20. H3.3 Explain the mechanisms used by the ileum to absorb and transport food, including facilitated diffusion, active transport, and endocytosis.

21. H3.3 Explain the mechanisms used by the ileum to absorb and transport food, including facilitated diffusion, active transport, and endocytosis.