RNA polymerase [OCHOA 1953] has _________ polypeptide chains.

Explanation

To answer the question about the number of polypeptide chains in RNA polymerase, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding RNA Polymerase**:
- RNA polymerase is an enzyme that plays a crucial role in the process of transcription, where it synthesizes RNA from a DNA template.

2. **Identifying the Structure**:
- RNA polymerase is a multi-subunit enzyme, meaning it is composed of several polypeptide chains.

3. **Counting the Polypeptide Chains**:
- The specific RNA polymerase enzyme discussed (Ochoa's RNA polymerase) consists of 5 polypeptide chains.
- These chains can be categorized as follows:
- 2 alpha chains
- 1 beta chain
- 1 beta prime chain
- 1 omega chain

4. **Conclusion**:
- Therefore, RNA polymerase has a total of **5 polypeptide chains**.

### Final Answer:
RNA polymerase has **5 polypeptide chains**.

---