Calvin reactions take place in grana of the chloroplast.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Statement**: The question states that Calvin reactions take place in the grana of the chloroplast. We need to evaluate the accuracy of this statement.

2. **Identifying the Location of Calvin Reactions**: The Calvin cycle, also known as the Calvin-Benson cycle, is a series of biochemical reactions that occur during photosynthesis. It is important to note that these reactions do not occur in the grana.

3. **Correct Location**: The Calvin reactions actually take place in the stroma of the chloroplast, not in the grana. The grana are primarily involved in the light-dependent reactions of photosynthesis, where light energy is converted into chemical energy.

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