Which of the following statement is correct ?

Options

A. The breakdown of most of biomacro molecules occurs in ileum.
B. Simple substance (digested foods) are completely absorbed in the duodenum
C. No significant digestive acitivity occurs in large intestine.
D. digested and absorbed substances are passed on to the large intestine.

Answer

To determine which statement is correct regarding the digestive system, we will analyze each option step by step.

### Step-by-Step Solution:

1. **Analyze the First Statement:**
- The statement claims that the breakdown of most bio-macromolecules occurs in the ileum.
- The ileum is indeed a part of the small intestine, but the primary site for the breakdown of bio-macromolecules (like proteins, carbohydrates, and fats) is the duodenum, not the ileum.
- **Conclusion:** This statement is incorrect.

2. **Analyze the Second Statement:**
- This statement suggests that simple substances or digested food will be completely absorbed in the duodenum.
- While the duodenum does play a significant role in digestion and absorption, not all absorption occurs here. Absorption also takes place in the jejunum and ileum, and some substances can be absorbed in the stomach and large intestine as well.
- **Conclusion:** This statement is incorrect.

3. **Analyze the Third Statement:**
- The statement claims that no significant digestive activity occurs in the large intestine.
- This is true; the large intestine primarily absorbs water, minerals, and some drugs, but it does not engage in significant digestion of food. The food that reaches the large intestine is mostly undigested or unabsorbed.
- **Conclusion:** This statement is correct.

4. **Analyze the Fourth Statement:**
- This statement implies that undigested food is passed on to the large intestine.
- While it is true that undigested food reaches the large intestine, the statement does not provide a complete picture of the large intestine's functions, which include absorption of water and electrolytes.
- **Conclusion:** This statement is partially true but does not address the main functions of the large intestine.

### Final Conclusion:
The correct statement among the options provided is the third statement, which indicates that no significant digestive activity occurs in the large intestine.

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