Which of the following processes does not contribute to the `CO_(2)` pool in the atmosphere?
1) Respiration by producers
2) Photosynthesis by producers
3) Respiration by consumers
4) Decomposition by decomposers.

Options

A. Respiration by producers
B. Photosynthesis by producers
C. Respiration by consumers
D. Decomposition by decomposers.

Answer

To solve the question of which process does not contribute to the CO₂ pool in the atmosphere, we will analyze each option step by step.

### Step 1: Analyze Respiration by Producers
- **Explanation**: Producers, such as plants, undergo respiration. During this process, they convert glucose and oxygen into energy, releasing carbon dioxide (CO₂) as a byproduct.
- **Contribution to CO₂ Pool**: Yes, respiration by producers contributes to the CO₂ pool.

### Step 2: Analyze Photosynthesis by Producers
- **Explanation**: Photosynthesis is the process by which producers (mainly plants) use sunlight, water, and carbon dioxide to produce glucose (starch) and oxygen. In this process, carbon dioxide is absorbed from the atmosphere.
- **Contribution to CO₂ Pool**: No, photosynthesis does not contribute to the CO₂ pool; instead, it reduces the amount of CO₂ in the atmosphere.

### Step 3: Analyze Respiration by Consumers
- **Explanation**: Consumers, which include animals and humans, also undergo respiration. They take in oxygen and glucose and release carbon dioxide as a byproduct.
- **Contribution to CO₂ Pool**: Yes, respiration by consumers contributes to the CO₂ pool.

### Step 4: Analyze Decomposition by Decomposers
- **Explanation**: Decomposers, such as bacteria and fungi, break down dead organic matter. This process also releases carbon dioxide into the atmosphere.
- **Contribution to CO₂ Pool**: Yes, decomposition by decomposers contributes to the CO₂ pool.

### Conclusion
After analyzing all the options, we find that the only process that does not contribute to the CO₂ pool in the atmosphere is **Photosynthesis by producers** (Option 2).

### Final Answer
**The correct answer is Option 2: Photosynthesis by producers.**

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