Explain how organ systems contribute to the organisation of a multicellular organism. Use the digestive system as an example in your answer.
Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).
Model answer (4 marks)
An organ system is a group of organs that work together to perform a function. Organs are aggregations of tissues that carry out a specific task. For example, the stomach is an organ of the digestive system; it secretes gastric juices that contain protease to digest food. The small intestine is another organ; it absorbs the digested nutrients into the bloodstream. The pancreas is an organ that produces digestive enzymes, and the liver is an organ that produces bile to aid fat digestion.
Examiner tips
- Define an organ system and an organ, then give a named organ and its function.
- Use specific terminology (e.g., protease, bile, absorption).
- Show clear link between organ function and system organisation.
Common mistakes
- Failing to name a specific organ from the digestive system.
- Using vague terms like "helps digestion" instead of specific functions.
- Not linking the organ’s function back to the overall system organisation.
Mark scheme (4 marks)
- An organ system is a group of organs that work together
- Organs are aggregations of tissues performing specific functions
- A named organ from the digestive system correctly identified (e.g. stomach, small intestine, pancreas, liver)
- The named organ performs a specific function within the digestive system (e.g. stomach digests food / produces protease; small intestine absorbs digested food; pancreas produces enzymes; liver produces bile)
Key terms in this question
organ systems · digestive system
Related
- Revision notes: Principles of organisation →
- How to answer a "Explain" question →
- Decode the mark scheme abbreviations →
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