If `CO_2` is given off in respiration, why does the amount of `CO_2` in the atmosphere remains relatively constant

Options

A. `CO_2` forms carbonate rocks
B. `CO_2` is buffer
C. `CO_2` is converted in photosynthesis to carbohydrates
D. `CO_2` splits up during photosynthesis

Explanation

To answer the question of why the amount of carbon dioxide (CO₂) in the atmosphere remains relatively constant despite being released during respiration, we can break down the explanation into several steps:

### Step-by-Step Solution:

1. **Understanding Respiration**:
- During respiration, organisms (including plants) break down carbohydrates to release energy. This process produces carbon dioxide (CO₂) as a byproduct.

2. **Understanding Photosynthesis**:
- Plants also carry out photosynthesis, a process where they use sunlight to convert carbon dioxide (CO₂) and water into glucose (a carbohydrate) and oxygen (O₂). This process occurs primarily in the chloroplasts of plant cells.

3. **Balance Between Respiration and Photosynthesis**:
- The key to understanding the constant levels of CO₂ in the atmosphere lies in the balance between respiration and photosynthesis. While respiration releases CO₂, photosynthesis absorbs CO₂.

4. **Carbon Fixation**:
- During photosynthesis, CO₂ is fixed into organic molecules (like glucose). This means that for every molecule of CO₂ released during respiration, an equivalent amount is absorbed during photosynthesis.

5. **Natural Carbon Cycle**:
- The natural carbon cycle involves the continuous exchange of CO₂ between the atmosphere, plants, animals, and the earth. This cycle helps maintain a relatively stable concentration of CO₂ in the atmosphere.

6. **Conclusion**:
- Therefore, the amount of CO₂ in the atmosphere remains relatively constant because the CO₂ produced during respiration is balanced by the CO₂ consumed during photosynthesis.

### Final Answer:
The amount of CO₂ in the atmosphere remains relatively constant because the carbon dioxide released during respiration is absorbed by plants during photosynthesis, where it is converted into carbohydrates.

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