Study the following statements. The correct statements are ,,
(I) the diameter of ribosomes is `230A^0`
(II) eukaryotes and Prokaryotes have both 80 S and 70 S ribosomes
(III) 80 S ribosomes are formed by association between 50 S and 30 S sub units
(IV) Polyribosomes translate and produce different polypeptides

Options

A. I only
B. I and III only
C. I, II and III only
D. II and IV

Answer

To determine which statements about ribosomes are correct, let's analyze each statement step by step.

### Step-by-Step Solution:

1. **Statement I: The diameter of ribosomes is 230 Å.**
- Ribosomes are indeed composed of proteins and ribosomal RNA (rRNA). The average diameter of ribosomes is approximately 230 Å (angstroms).
- **Conclusion:** This statement is **correct**.

2. **Statement II: Eukaryotes and prokaryotes have both 80S and 70S ribosomes.**
- Eukaryotic ribosomes are classified as 80S, while prokaryotic ribosomes are classified as 70S. Eukaryotes do not have 70S ribosomes, and prokaryotes do not have 80S ribosomes.
- **Conclusion:** This statement is **incorrect**.

3. **Statement III: 80S ribosomes are formed by the association between 50S and 30S subunits.**
- This statement is incorrect because 80S ribosomes are formed by the association of 60S and 40S subunits (in eukaryotes), while 70S ribosomes are formed by the association of 50S and 30S subunits (in prokaryotes).
- **Conclusion:** This statement is **incorrect**.

4. **Statement IV: Polyribosomes translate and produce different polypeptides.**
- Polyribosomes (or polysomes) consist of multiple ribosomes translating a single mRNA strand simultaneously. They produce the same polypeptide chain, not different ones.
- **Conclusion:** This statement is **incorrect**.

### Summary of Correct Statements:
- The only correct statement is **Statement I**.

### Final Answer:
- The correct answer is **Option 1** (only Statement I is correct).