During human digestion, complex insoluble macromolecules must be broken down by specific enzymes into smaller, soluble molecules before they can be absorbed into the bloodstream.
Complete the table below by identifying the missing substances represented by (i), (ii), and (iii).
| Large nutrient molecule | Enzyme involved in digestion | Product(s) of digestion |
|---|---|---|
| Starch | Amylase | (i) |
| Protein | (ii) | Amino acids |
| (iii) | Lipase | Fatty acids and glycerol |
Following chemical digestion, these small soluble molecules are absorbed across the wall of the ileum (small intestine). Describe three structural features of the ileum wall that facilitate rapid absorption into the circulatory system.
65 exam-style questions on Edexcel IGCSE Biology Nutrition. Each one has a worked solution and a mark scheme showing where the marks go.