Rickettsiae is a group of

Options

A. Viruses
B. microorganisms
C. Bacteria
D. PPLO.

Answer

**Step-by-Step Solution:**

1. **Understanding Rickettsiae**: Rickettsiae are a group of microorganisms that are classified under the category of bacteria. They are known for their unique characteristics and behavior.

2. **Classification**: Rickettsiae are specifically classified as gram-negative bacteria. This classification is based on their cell wall structure, which does not retain the crystal violet stain used in the Gram staining procedure.

3. **Life Cycle**: Rickettsiae are obligate intracellular parasites, meaning they can only reproduce and complete their life cycle within the cells of a host organism. This distinguishes them from many other bacteria that can live independently.

4. **Transmission**: These bacteria are primarily transmitted through arthropods, which serve as vectors. Common vectors include ticks, fleas, and lice, which can carry Rickettsiae and transmit them to their hosts.

5. **Cell Structure**: Rickettsiae possess a cell wall, which is a typical feature of bacteria. However, they are non-flagellated, meaning they do not have flagella for movement.

6. **Conclusion**: Based on the characteristics and classification of Rickettsiae, we conclude that they belong to the group of bacteria.

**Final Answer**: Rickettsiae is a group of **bacteria**.

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