A prokaryotic autotrophic nitrogen fixing symbiont is found in

Options

A. Cicer
B. Cycas
C. Pisum
D. Alnus.

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks about a prokaryotic autotrophic nitrogen-fixing symbiont. We need to identify the organism and the specific context in which it is found.

2. **Identifying Prokaryotic Autotrophs**: Prokaryotic autotrophs are organisms that can produce their own food through photosynthesis or chemosynthesis and lack a defined nucleus. Cyanobacteria are a well-known group of prokaryotic autotrophs.

3. **Nitrogen Fixation**: Nitrogen fixation is the process by which nitrogen in the atmosphere is converted into ammonia by certain bacteria. Cyanobacteria are capable of nitrogen fixation, making them important in ecosystems.

4. **Symbiotic Relationships**: The question specifies a symbiotic relationship, which means the organism lives in close association with another organism, often to the mutual benefit of both.

5. **Cyanobacteria in Symbiosis**: In the context of symbiosis, cyanobacteria are often found in association with certain plants. One notable example is their relationship with cycads.

6. **Specific Example**: The specific cyanobacterium mentioned in the video is "Anabaena," which is a type of blue-green algae. Anabaena is commonly found in the coralloid roots of cycads.

7. **Conclusion**: Therefore, the prokaryotic autotrophic nitrogen-fixing symbiont is found in cycads, specifically in the coralloid roots where cyanobacteria like Anabaena reside.

**Final Answer**: A prokaryotic autotrophic nitrogen-fixing symbiont is found in cycads, specifically in the coralloid roots.

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