Ammonia , urea uric acid , carbon dioxide , water and pons like `Na^+,K^+,Cl^+` Phosphate, sulfate, etc., are

Options

A. Excretory substances
B. Metabolic products
C. Respiratory substances
D. both (a) and b)

Answer

To solve the question regarding ammonia, urea, uric acid, carbon dioxide, water, and ions like Na^+, K^+, Cl^-, phosphate, sulfate, etc., we need to categorize these substances based on their roles in biological systems. Here's a step-by-step breakdown:

### Step 1: Identify the Nature of Each Substance
- **Ammonia, Urea, Uric Acid**: These are nitrogenous waste products resulting from protein metabolism in animals. They are primarily excretory products.
- **Carbon Dioxide and Water**: These are products of cellular respiration and metabolic processes. They are also involved in photosynthesis in plants.
- **Ions (Na^+, K^+, Cl^-, Phosphate, Sulfate)**: These are essential minerals and nutrients that play critical roles in cellular functions, including nerve transmission, muscle contraction, and metabolic processes.

### Step 2: Classify the Substances
- **Excretory Products**: Ammonia, Urea, Uric Acid (these are primarily produced and excreted by animals).
- **Metabolic Products**: Carbon Dioxide, Water, and the ions (Na^+, K^+, Cl^-, Phosphate, Sulfate) can be considered metabolic products as they are involved in various metabolic activities within organisms.

### Step 3: Conclusion
Based on the classifications:
- Ammonia, Urea, and Uric Acid are excretory substances.
- Carbon Dioxide, Water, and the ions are metabolic products.

Thus, the correct answer to the question is that both categories are valid: they include excretory substances and metabolic products.

### Final Answer
Both A (Excretory substances) and B (Metabolic products) are correct.

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