Excretion is removal of

Options

A. Carbon dioxide
B. Harmful and useless ingredients
C. Extra water
D. Metabolic waste products

Answer

**Step-by-Step Text Solution:**

1. **Understanding Excretion:**
- Excretion refers to the process of removing waste products from the body. It is essential for maintaining homeostasis and ensuring that toxic substances do not accumulate in the body.

2. **Identifying the Types of Waste:**
- The waste products that are typically excreted include metabolic waste products such as carbon dioxide, urea, ammonia, uric acid, and guanine. These substances are byproducts of various metabolic processes occurring in the body.

3. **Importance of Excretion:**
- The removal of these metabolic wastes is crucial because they can be toxic to cells and can interfere with the body's metabolic activities if allowed to accumulate.

4. **Excretory Organs:**
- Various organs are involved in the excretion process. The lungs excrete carbon dioxide, the skin can excrete some waste products, and the kidneys are the primary organs responsible for filtering and excreting metabolic waste products from the blood.

5. **Analyzing the Options:**
- The question provides multiple options regarding what excretion removes:
- **Carbon dioxide**: While it is excreted, it is not the sole focus of excretion.
- **Harmful and useless ingredients**: This is too vague and not specific to metabolic waste.
- **Extra water**: While water balance is important, excretion primarily refers to metabolic waste products.
- **Metabolic waste products**: This is the most accurate description of what excretion entails.

6. **Conclusion:**
- Based on the analysis, the correct answer to the question "Excretion is the removal of" is **metabolic waste products**.

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