Which of the following statements is false?

Options

A. (a) The breakdown of most of the biomacromolecules occurs in duodenum.
B. (b) Simple substances (digested foods) are absorbed in the jejunum and ileum.
C. (c) Significant digestive activity occurs in large intestine.
D. (d) Undigested and unabsorbed substances are passed on to the large intestine.

Explanation

To determine which statement is false among the given options, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Analyze Statement A**:
- Statement A claims that "the breakdown of most of the biomacromolecules occurs in the duodenum."
- **Explanation**: This statement is true. The duodenum is the first part of the small intestine where most of the digestion occurs, aided by bile and pancreatic juices.

2. **Analyze Statement B**:
- Statement B states that "simple substances, the digestive food are absorbed in the jejunum and ileum."
- **Explanation**: This statement is also true. The jejunum and ileum are responsible for the absorption of nutrients, and they have structures called villi that increase the surface area for absorption.

3. **Analyze Statement C**:
- Statement C claims that "significant digestive activity occurs in the large intestine."
- **Explanation**: This statement is false. The large intestine primarily functions in water absorption and the formation of feces. There is no significant digestive activity occurring in the large intestine as all digestion is completed in the small intestine.

4. **Analyze Statement D**:
- Statement D states that "undigested matter and unabsorbed substances are passed on to the large intestine."
- **Explanation**: This statement is true. After digestion and absorption in the small intestine, any undigested and unabsorbed materials are passed to the large intestine.

### Conclusion:
- The only false statement among the options is **Statement C**: "Significant digestive activity occurs in the large intestine."

### Final Answer:
- **The correct answer is option C**: Significant digestive activity occurs in the large intestine is the false statement.

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