Describe the roles of the large intestine in processing undigested food material.
Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).
Model answer (4 marks)
Water is absorbed in the large intestine, reducing the volume of the material.
Mineral salts and ions are absorbed, helping to maintain electrolyte balance.
Undigested material is stored and compacted as faeces in the rectum.
Faeces are removed from the body through the anus by egestion.
Mineral salts and ions are absorbed, helping to maintain electrolyte balance.
Undigested material is stored and compacted as faeces in the rectum.
Faeces are removed from the body through the anus by egestion.
Examiner tips
- Use the exact terms: 'absorbed', 'compact', 'faeces', 'egestion'.
- Show the sequence: absorption → storage → removal.
- Keep each point brief but complete.
Common mistakes
- Confusing the small intestine with the large intestine for absorption.
- Using 'eliminated' instead of 'egestion' for the final step.
- Omitting the role of mineral salts/ions in the answer.
Mark scheme (4 marks)
- Water is absorbed/reabsorbed in the large intestine
- Mineral salts / ions are absorbed in the large intestine
- Undigested material is stored / compacted as faeces in the rectum
- Faeces are removed from the body through the anus by egestion
Key terms in this question
Related
- All Cambridge International IGCSE Biology (0610) revision notes →
- How to answer a "Describe" question →
- Decode the mark scheme abbreviations →