Chemically ribosomes are composed of

Options

A. RNA and protein
B. r- RNA, protein and DNA
C. RNA , protein & lipid
D. none of these

Answer

### Step-by-Step Solution:

1. **Understanding Ribosomes**:
- Ribosomes are cellular structures responsible for protein synthesis. They are often referred to as the "protein factories" of the cell.

2. **Chemical Composition**:
- Ribosomes are composed of two main components: ribonucleic acid (RNA) and proteins.

3. **Types of Ribosomes**:
- There are two types of ribosomes based on the type of organism:
- Prokaryotic ribosomes (70S)
- Eukaryotic ribosomes (80S)

4. **Subunit Structure**:
- Both prokaryotic and eukaryotic ribosomes consist of two subunits:
- Prokaryotes: Large subunit (50S) and small subunit (30S)
- Eukaryotes: Large subunit (60S) and small subunit (40S)

5. **Absence of Membrane**:
- Ribosomes are not surrounded by any membrane, distinguishing them from other cellular organelles.

6. **Conclusion**:
- Given the options provided, the correct answer is that ribosomes are composed of RNA and proteins.

### Final Answer:
Ribosomes are chemically composed of RNA and proteins.

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