Oxygenic photosynthesis occurs in

Options

A. Oscillatoria
B. Rhodospirillum
C. Chlorobium
D. Chromatium

Answer

To solve the question "Oxygenic photosynthesis occurs in," we will analyze the options provided and understand the concept of oxygenic photosynthesis.

### Step-by-Step Solution:

1. **Understanding Oxygenic Photosynthesis**:
- Oxygenic photosynthesis is a process where light energy is used to convert carbon dioxide and water into glucose and oxygen. The oxygen produced is a byproduct of this process.
- This type of photosynthesis occurs in organisms that contain chlorophyll, which is essential for capturing light energy.

2. **Identifying the Organisms**:
- We need to evaluate the options given in the question to determine which organism is capable of oxygenic photosynthesis.

3. **Analyzing the Options**:
- **Option 1: Oscillatoria**:
- Oscillatoria is a type of cyanobacteria that contains chlorophyll. Cyanobacteria are known for performing oxygenic photosynthesis, as they can produce oxygen from water.
- **Option 2: Rhodospirillum**:
- Rhodospirillum is an anaerobic bacterium that does not require oxygen for its metabolic processes. It does not perform oxygenic photosynthesis.
- **Option 3: Chlorobium**:
- Chlorobium is a type of green sulfur bacteria that performs anoxygenic photosynthesis, which does not produce oxygen.
- **Option 4: Chromatium**:
- Chromatium is also a type of green sulfur bacteria and performs anoxygenic photosynthesis, similar to Chlorobium.

4. **Conclusion**:
- Based on the analysis, the only organism from the options that performs oxygenic photosynthesis is **Oscillatoria**.

### Final Answer:
Oxygenic photosynthesis occurs in **Oscillatoria**.

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