Which one of the following pair of waste substances is removed from blood in ornithine cycle `:`

Options

A. `CO_(2)` and urea
B. Ammonia and urea
C. `CO_(2)` and ammonia
D. Urea and sodium salt

Answer

To solve the question regarding which pair of waste substances is removed from blood in the ornithine cycle, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Ornithine Cycle**: The ornithine cycle, also known as the urea cycle, primarily occurs in the liver. It is a biochemical process that converts ammonia, which is highly toxic, into urea, which is less toxic and can be excreted from the body.

2. **Identify the Components**: The main components involved in the ornithine cycle are ammonia (NH3) and carbon dioxide (CO2). These two substances react together in the presence of specific enzymes.

3. **Reaction Process**: In the cycle, ammonia (NH3) combines with carbon dioxide (CO2) to form urea. This process is crucial because it helps in detoxifying ammonia, which is produced from protein metabolism.

4. **Evaluate the Options**: Now, let's analyze the given options:
- **CO2 and Urea**: This is incorrect because CO2 is not removed; it is a reactant.
- **Ammonia and Urea**: This is incorrect because urea is the product formed, not removed.
- **CO2 and Ammonia**: This is the correct answer because both CO2 and ammonia are involved in the cycle, and they react to form urea.
- **Urea and Sodium Salt**: This is incorrect as sodium salt is not a waste product of the ornithine cycle.

5. **Conclusion**: The correct answer is the pair of waste substances that are removed from blood in the ornithine cycle, which is **CO2 and Ammonia**.

### Final Answer:
The correct option is **CO2 and Ammonia**.

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