The `CO_(2)` fixation during the Hatch and Slack pathway occurs in

Options

A. Large thick walled cells
B. Mesophyll cells
C. Vascular bundles
D. Bundle sheath cell cytoplasm

Answer

**Step-by-Step Solution:**

1. **Understanding the Pathway**: The Hatch and Slack pathway is also known as the C4 pathway, which is a method of carbon fixation in certain plants, particularly those adapted to high temperatures and dry environments.

2. **Identifying the Location of CO2 Fixation**: In the C4 pathway, the initial fixation of carbon dioxide occurs in specific cells. The key cells involved in this process are the mesophyll cells and the bundle sheath cells.

3. **Role of Mesophyll Cells**: The mesophyll cells are responsible for the first step of carbon dioxide fixation. In these cells, carbon dioxide is combined with phosphoenol pyruvate (PEP) through the action of the enzyme PEP carboxylase.

4. **Formation of C4 Acid**: The reaction in the mesophyll cells results in the formation of a four-carbon compound, commonly referred to as C4 acid. This compound is then transported to the bundle sheath cells.

5. **Conversion in Bundle Sheath Cells**: In the bundle sheath cells, the C4 acid is converted into a three-carbon compound (C3 acid), which is then utilized in the Calvin cycle for further processing.

6. **Conclusion**: Therefore, the carbon dioxide fixation during the Hatch and Slack pathway occurs specifically in the mesophyll cells.

**Final Answer**: The CO2 fixation during the Hatch and Slack pathway occurs in the **mesophyll cells**.

---