Pollen grains are nongreen due to

Options

A. Absence of plastids
B. Degeneration of plastids
C. Conversion of plastids into chromoplasts
D. Attraction of vectors.

Answer

**Step-by-Step Solution:**

1. **Understanding Pollen Grains**: Pollen grains are the male gametophytes of seed plants and are typically yellow in color.

2. **Role of Plastids**: Plastids are organelles found in plant cells that can be colorless or colored. The main types of plastids relevant to this discussion are chloroplasts and chromoplasts.

3. **Chloroplasts and Green Color**: Chloroplasts are a type of plastid that contain chlorophyll, the pigment responsible for the green color in plants. They are primarily involved in photosynthesis.

4. **Chromoplasts and Other Colors**: Chromoplasts are another type of plastid that contain various pigments, which can give flowers and fruits their red, orange, or yellow colors. However, they do not contain chlorophyll.

5. **Pollen Grain Composition**: In pollen grains, the plastids undergo a transformation into chromoplasts. This conversion results in the absence of chlorophyll, leading to the non-green color of pollen grains.

6. **Conclusion**: Therefore, pollen grains are non-green due to the conversion of plastids into chromoplasts, which do not contain chlorophyll.

**Final Answer**: Pollen grains are non-green due to the conversion of plastids into chromoplasts, which lack chlorophyll.

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