Frankia is a

Options

A. fungi
B. actinomycetes
C. cyanobacteria
D. alga

Answer

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

1. **Identify the Organism**: The question asks about Frankia, which is a type of organism. We need to determine whether it is a fungi, actinomycetes, cyanobacteria, or algae.

2. **Understanding Frankia**: Frankia is known to be a genus of bacteria. Specifically, it belongs to the group called actinomycetes. This is a significant point because actinomycetes are known for their role in various ecological processes.

3. **Role in Nitrogen Fixation**: Frankia is particularly important because it is capable of nitrogen fixation. This means that it can convert atmospheric nitrogen (N₂) into ammonia (NH₃) or other nitrogenous compounds that plants can use for growth.

4. **Symbiotic and Free-Living Conditions**: Frankia can fix nitrogen both in symbiotic relationships with certain plants and as a free-living organism in the soil. This versatility allows it to play a crucial role in soil fertility.

5. **Classification**: Frankia is classified as a gram-positive, aerobic bacterium that is part of the actinomycetes group. This classification helps in understanding its characteristics and functions.

6. **Eliminating Incorrect Options**:
- Fungi: Frankia is not a fungus.
- Cyanobacteria: While cyanobacteria are also involved in nitrogen fixation, they are photosynthetic bacteria and not the same as Frankia.
- Algae: Algae are eukaryotic organisms and not related to Frankia.

7. **Conclusion**: Based on the information, the correct classification of Frankia is that it is an actinomycete, specifically a nitrogen-fixing bacterium.

**Final Answer**: Frankia is an actinomycete.

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