Compared to many other organisms, which group show the most extensive metabolic deversity?

Answer

### Step-by-Step Solution:

1. **Understanding Metabolic Diversity**:
- Metabolic diversity refers to the various ways organisms obtain energy and nutrients. It encompasses different metabolic pathways and strategies that organisms use to survive and thrive in their environments.

2. **Identifying the Group with Extensive Metabolic Diversity**:
- Among all living organisms, bacteria exhibit the most extensive metabolic diversity. This is due to their ability to adapt to various environments and utilize a wide range of energy sources.

3. **Types of Bacteria**:
- Bacteria can be classified into two main categories based on their nutritional needs:
- **Autotrophic Bacteria**: These bacteria can produce their own food.
- **Heterotrophic Bacteria**: These bacteria cannot produce their own food and rely on other organisms for nutrition.

4. **Subcategories of Autotrophic Bacteria**:
- Autotrophic bacteria are further divided into:
- **Photosynthetic Bacteria**: They obtain energy from sunlight. Examples include Rhodospirulum and Chlorobium.
- **Chemosynthetic Bacteria**: They obtain energy by oxidizing inorganic substances. Examples include Nitrosomonas and Nitrobacter.

5. **Subcategories of Heterotrophic Bacteria**:
- Heterotrophic bacteria are divided into:
- **Parasitic Bacteria**: These bacteria derive nutrients from living hosts.
- **Saprophytic Bacteria**: They obtain nutrients from dead organic matter.
- **Symbiotic Bacteria**: They engage in mutualistic relationships with other organisms, benefiting both parties. An example is Rhizobium, which helps in nitrogen fixation in legumes.

6. **Conclusion**:
- The extensive metabolic diversity of bacteria is due to their varied nutritional strategies, which include both autotrophic and heterotrophic modes of nutrition. This diversity allows them to thrive in a wide range of environments, making them one of the most versatile groups of organisms.