Which of the following types of ribosomal RNA is not present in eukaryotic cytoplasm ?

Options

A. 18S
B. 28S
C. 5.8S
D. 16S

Answer

To solve the question regarding which type of ribosomal RNA is not present in eukaryotic cytoplasm, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Types of Ribosomal RNA (rRNA)**:
- In eukaryotic cells, the main types of rRNA include:
- 28S rRNA
- 18S rRNA
- 5.8S rRNA
- 5S rRNA
- These rRNAs are components of the ribosomes found in the cytoplasm.

2. **Identify the rRNA Types Present in Prokaryotes**:
- Prokaryotic cells, such as bacteria, contain:
- 16S rRNA (part of the small ribosomal subunit)
- 23S rRNA and 5S rRNA (part of the large ribosomal subunit)

3. **Determine Which rRNA is Absent in Eukaryotic Cytoplasm**:
- Among the types mentioned, 16S rRNA is specifically associated with prokaryotic ribosomes and is not found in eukaryotic cells.

4. **Conclusion**:
- Therefore, the type of ribosomal RNA that is not present in eukaryotic cytoplasm is **16S rRNA**.

### Final Answer:
**16S rRNA is not present in eukaryotic cytoplasm.**

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