Find odd one w.r.t. phototrophic nutrition

Options

A. Chromatium and Chlorobium
B. Rhodopseudomonas and Thiospirillium
C. Chloronema and Chloroflexus
D. Pseudomonas and Clostridium

Answer

To solve the question of finding the odd one with respect to phototrophic nutrition, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Phototrophic Nutrition**:
- Phototrophic nutrition is a type of autotrophic nutrition where organisms produce their own food using sunlight through the process of photosynthesis.

2. **Identify the Types of Organisms**:
- We need to analyze the options provided and identify which organisms are capable of phototrophic nutrition and which are not.

3. **Examine the Given Options**:
- **Option 1**: Chromatium and Chlorobium
- Chromatium is a purple sulfur bacterium that can perform both chemoautotrophy and photoautotrophy.
- Chlorobium is a green sulfur bacterium that is a photoautotroph.
- Both are capable of phototrophic nutrition.

- **Option 2**: Rhodopseudomonas and Thiospirillum
- Both are types of bacteria that can perform phototrophic nutrition.
- Hence, this option is not the odd one out.

- **Option 3**: Chloronema and Chloroflexus
- Both organisms are also phototropic and capable of photosynthesis.
- Therefore, this option is not the odd one out either.

4. **Identify the Odd One Out**:
- **Option 4**: Pseudomonas and Clostridium
- Both are known to be heterotrophic and parasitic, depending on other organisms for their nutrition.
- They do not perform phototrophic nutrition, making this option the odd one out.

5. **Conclusion**:
- The odd one with respect to phototrophic nutrition is **Pseudomonas and Clostridium** as they are not capable of photosynthesis and depend on other organisms for food.

### Final Answer:
The odd one with respect to phototrophic nutrition is **Pseudomonas and Clostridium**.