Describe the role of enzymes in the digestion of carbohydrates, naming the enzyme involved and the products formed.
Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).
Model answer (4 marks)
Amylase, an enzyme produced in the salivary glands and the pancreas, hydrolyses starch into maltose and other small sugars.
In the small intestine, the enzyme maltase further breaks down maltose into glucose.
The final products of carbohydrate digestion are glucose molecules, which can be absorbed into the bloodstream.
In the small intestine, the enzyme maltase further breaks down maltose into glucose.
The final products of carbohydrate digestion are glucose molecules, which can be absorbed into the bloodstream.
Examiner tips
- Use the exact terms "amylase" and "maltase". Show the stepwise breakdown: starch → maltose → glucose. Mention the sites of enzyme production (salivary glands, pancreas, small intestine).
- Keep the answer concise – 4 marks can be earned with 4 short points.
Mark scheme (4 marks)
- Amylase breaks down starch (a carbohydrate)
- Amylase is produced in the salivary glands and/or the pancreas
- Starch is broken down into maltose / sugars
- Maltose is further broken down into glucose by maltase (in the small intestine)
Related
- All WJEC GCSE Biology (Wales) revision notes →
- How to answer a "Describe" question →
- Decode the mark scheme abbreviations →