In many cells ribosomes occur in chains along messenger RNA. What is the advantage of this arrangement as compared to a situation in which ribosomes occur singly?

Options

A. A greater variety of polypeptides can be produced
B. Polypeptides can be produced more rapidly
C. Fewer RNA molecules are used in protein synthesis
D. The probability of gene mutation occurring is less

Answer

### Step-by-Step Solution:

1. **Understanding Ribosome Function**: Ribosomes are the cellular machinery responsible for protein synthesis. They translate messenger RNA (mRNA) into polypeptides (proteins).

2. **Ribosome Arrangement**: In many cells, ribosomes can be found in chains along the mRNA. This arrangement is known as a polysome or polyribosome.

3. **Comparison of Arrangements**:
- **Single Ribosomes**: If ribosomes were to occur singly, each ribosome would translate the mRNA independently. This means that only one ribosome would be synthesizing a polypeptide at a time.
- **Ribosomes in Chains**: When ribosomes are arranged in chains, multiple ribosomes can translate the same mRNA strand simultaneously. This allows for the production of multiple copies of the same polypeptide in a shorter amount of time.

4. **Advantages of Ribosomes in Chains**:
- **Increased Efficiency**: The simultaneous translation by multiple ribosomes leads to a more rapid production of polypeptides.
- **Higher Yield**: More proteins can be synthesized from a single mRNA molecule in a given timeframe, which is crucial for cellular functions that require a high amount of protein.

5. **Conclusion**: The primary advantage of ribosomes occurring in chains along mRNA is that polypeptides can be produced more rapidly compared to when ribosomes occur singly.

### Final Answer:
The correct answer is that polypeptides can be produced more rapidly when ribosomes occur in chains along the messenger RNA.

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