In a experiment on two leaves - a variegated leaf or a leaf that was partially covered with black paper, and one that was exposed to light. Testing these leaves for what so that it becomes clear that photosynthesis occurred only in the green parts of the leaves in the presence of light.

Options

A. glucose
B. starch
C. maltose
D. protein

Answer

To determine whether photosynthesis occurred in the green parts of the leaves, we can follow these steps:

### Step-by-Step Solution:

1. **Select the Leaves**: Choose two leaves for the experiment. One should be a variegated leaf (a leaf that has both green and non-green parts) or a leaf that has been partially covered with black paper, and the other should be a fully green leaf exposed to light.

2. **Expose the Leaves to Light**: Place the variegated leaf and the fully green leaf in sunlight for a specific duration. This allows the leaves to undergo photosynthesis, particularly in the green parts.

3. **Bleach the Leaves**: After exposure to light, bleach both leaves to remove chlorophyll. This will turn the green parts of the leaves white, making it easier to test for the presence of starch.

4. **Iodine Staining**: Treat the bleached leaves with iodine solution. Iodine is used because it reacts with starch to produce a blue-black color.

5. **Observe Color Change**:
- The bleached green parts of the leaf that were exposed to light should turn blue-black after iodine treatment, indicating the presence of starch, which means photosynthesis occurred in those parts.
- The bleached non-green parts of the variegated leaf (or the part covered with black paper) will remain white after iodine treatment, indicating that no starch was produced, and thus, photosynthesis did not occur in those areas.

6. **Conclusion**: From the color change, conclude that photosynthesis occurred only in the green parts of the leaves that were exposed to light, as evidenced by the formation of starch.