Digestive Enzyme
Contents
Key Stage 3
Meaning

The digestive enzyme shown in purple attaches to the substrate which is broken down into two smaller pieces.
A digestive enzyme is a molecule made in the digestive system that breaks down large food molecules into smaller molecules.
About Digestive Enzymes
- There are different digestive enzymes for each nutrient.
Some digestive enzymes you should know:
- Carbohydrase - Breaks down complex carbohydrates into simple sugars.
- Protease - Breaks down proteins.
- Lipase - Breaks down lipids (fats and oils).
Key Stage 4
Meaning
A digestive enzyme is an enzyme which is used to break down large insoluble molecules into smaller soluble molecules.
About Digestive Enzymes
- Digestive enzymes, like all enzymes, are made of proteins.
- Digestive enzymes work as a catalyst for the breakdown of large molecules.
- Digestive enzymes are shaped to work on only one substrate. This called the Lock and Key Model.
Some digestive enzymes you should know:
- Carbohydrases - Salivary Amylase, Pancreatic Amylase and Amylase.
- Proteases - Pepsin, Trypsin and Peptidase
- Lipase
Digestive Enzyme | Breaks down... | into... | Produced by: |
Salivary Amylase | Starch | Maltose | The salivary glands in the mouth. |
Pancreatic Amylase | Starch | Maltose | The pancreas and released into the Small Intestine. |
Amylase | Maltose | Glucose | The Small Intestine. |
Pepsin | Protein | Amino Acids | The gastric glands in the stomach. |
Trypsin | Protein | Amino Acids | The pancreas and released into the Small Intestine. |
Peptidase | Protein | Amino Acids | The Small Intestine. |
Lipase | Lipids | Fatty Acids and Glycerol. | The Pancreas. |
References
AQA
- Digestive enzymes, page 27, GCSE Combined Science; The Revision Guide, CGP, AQA
- Digestive enzymes, pages 43, 45-50, GCSE Biology, Hodder, AQA
- Digestive enzymes, pages 46-7, GCSE Combined Science Trilogy 1, Hodder, AQA
- Digestive system, page 24, GCSE Combined Science; The Revision Guide, CGP, AQA
- Digestive system, pages 100-101, GCSE Biology; Student Book, Collins, AQA
- Digestive system, pages 27, 31, GCSE Biology; The Revision Guide, CGP, AQA
- Digestive system, pages 36, 41, 42-50, 66, GCSE Biology, Hodder, AQA
- Digestive system, pages 38-51, GCSE Biology; Third Edition, Oxford University Press, AQA
- Digestive system, pages 43-6, GCSE Combined Science Trilogy 1, Hodder, AQA
- Digestive system, pages 67, 116, GCSE Combined Science Trilogy; Biology, CGP, AQA
- Digestive system, pages 73, 122, GCSE Biology, CGP, AQA
- Digestive system; active transport in, page 37, GCSE Combined Science Trilogy 1, Hodder, AQA
- Digestive system; model of, page 66, GCSE Combined Science Trilogy 1, Hodder, AQA