Even though a very few cells in a `C_(4)` plant carry out the biosynthetic – Calvin pathway, yet they are highly productive. Can you discuss why?

Explanation

### Step-by-Step Solution:

1. **Understanding C4 Plants**: C4 plants have a unique photosynthetic pathway that differs from C3 plants. In C4 plants, the initial fixation of carbon dioxide occurs in mesophyll cells, where CO2 is combined with phosphoenolpyruvate (PEP) to form a four-carbon compound (C4 acid).

2. **Location of Calvin Cycle**: The Calvin cycle, which is the biosynthetic pathway for producing glucose, occurs in the bundle sheath cells of C4 plants. This is where the C4 acids produced in the mesophyll are transported and broken down to release CO2.

3. **Reduction of Photorespiration**: One of the key advantages of C4 plants is that they minimize photorespiration, a process that can waste energy and reduce the efficiency of photosynthesis. In C4 plants, the mechanism of concentrating CO2 around the enzyme RuBisCO (ribulose bisphosphate carboxylase/oxygenase) helps ensure that RuBisCO primarily functions as a carboxylase rather than an oxygenase.

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