Mark the incorrect statement with respect to single -cell protein .

Options

A. It is one of the alternate source of protein for animal and human nutrition
B. It involves growing of unicellular microbes only on industrial scale
C. They can be easily grown on materials like waste water.
D. Such utilisation also reduces environmental pollution .

Answer

To solve the question regarding the incorrect statement about single-cell protein, we will analyze each statement related to single-cell protein (SCP) and determine which one is incorrect.

### Step-by-Step Solution:

1. **Understanding Single-Cell Protein (SCP)**:
- Single-cell protein refers to the protein derived from the biomass of microorganisms such as bacteria, yeast, and algae. It serves as an alternative protein source for both human and animal nutrition.

2. **Analyzing the Statements**:
- **Statement 1**: "It is one of the alternate sources of protein for animal and human nutrition."
- This statement is correct as SCP is indeed used as a protein source for both animals and humans.

- **Statement 2**: "It involves growing of unicellular microbes only on an industrial scale."
- This statement is incorrect. While SCP primarily involves unicellular organisms, there are also multicellular organisms that can be used in SCP production. Therefore, stating that it involves only unicellular microbes is misleading.

- **Statement 3**: "They can be easily grown on materials like wastewater."
- This statement is correct. Many microorganisms used for SCP can thrive on waste materials, including wastewater, which helps in reducing environmental pollution.

- **Statement 4**: "Such utilization also reduces environmental pollution."
- This statement is also correct. Utilizing waste materials for SCP production can help mitigate pollution by recycling nutrients.

3. **Conclusion**:
- The incorrect statement is **Statement 2**, which claims that SCP involves only unicellular microbes. This is not entirely true as there are multicellular organisms that can also be utilized.

### Final Answer:
The incorrect statement with respect to single-cell protein is: **"It involves growing of unicellular microbes only on an industrial scale."**

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