Single cell proteins are

Options

A. Microorganisms
B. Enzymes
C. Antibiotics
D. Toxins

Answer

**Step-by-Step Solution:**

1. **Understanding Single Cell Proteins (SCP):**
- Single cell proteins refer to proteins derived from single-celled organisms, primarily microorganisms such as bacteria, yeast, and algae. They are rich in protein and can be used as a food supplement.

2. **Identifying the Options:**
- Option 1: Microorganisms
- Option 2: Enzymes
- Option 3: Antibiotics
- Option 4: Toxins

3. **Analyzing Each Option:**
- **Option 1: Microorganisms** - This is correct as SCP is derived from microorganisms that can produce large amounts of protein.
- **Option 2: Enzymes** - Incorrect, as enzymes are biological catalysts that speed up reactions but are not proteins themselves.
- **Option 3: Antibiotics** - Incorrect, as antibiotics are substances used to kill or inhibit the growth of bacteria, not to produce proteins.
- **Option 4: Toxins** - Incorrect, as toxins are harmful substances that can destroy proteins rather than create them.

4. **Conclusion:**
- The correct answer is **Option 1: Microorganisms**, as they are the source of single cell proteins.

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