Chlorophyll a occurs in

Options

A. all photosynthetic autotrophs
B. in all higher plants
C. all oxygen liberating autotrophs
D. all plants except fungi

Answer

**Step-by-Step Solution:**

1. **Understanding Chlorophyll a**: Chlorophyll a is a pigment essential for photosynthesis, allowing plants to absorb light energy, primarily from the blue and red wavelengths.

2. **Occurrence in Organisms**: Chlorophyll a is found in all photosynthetic organisms, which include higher plants, algae, and some bacteria. However, it is important to note that not all bacteria possess chlorophyll a.

3. **Photosynthetic Plants**: The primary groups of organisms that contain chlorophyll a are the oxygen-liberating autotrophs, which include:
- Higher plants (e.g., trees, shrubs, and flowering plants)
- Green algae
- Cyanobacteria (blue-green algae)

4. **Exclusion of Certain Bacteria**: While chlorophyll a is common in many photosynthetic organisms, it is not found in all bacteria. Some bacteria have different types of chlorophyll, such as bacteriochlorophyll.

5. **Conclusion**: Based on the information, chlorophyll a occurs in all oxygen-liberating autotrophs, which are primarily the photosynthetic plants.

6. **Final Answer**: Therefore, the correct option is that chlorophyll a occurs in all oxygen-liberating autotrophs.

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