Cell organelle present in both prokaryotic and eukaryotic cells is

Options

A. Ribosome
B. Mitochondria
C. ER
D. Nucleus

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for a cell organelle that is present in both prokaryotic and eukaryotic cells.

2. **Defining Prokaryotic and Eukaryotic Cells**: Prokaryotic cells are simpler, smaller cells without a nucleus or membrane-bound organelles (e.g., bacteria). Eukaryotic cells are more complex, larger cells that contain a nucleus and membrane-bound organelles (e.g., plant and animal cells).

3. **Identifying Common Organelles**: To find an organelle present in both types of cells, we need to consider the functions and structures common to all living cells.

4. **Focusing on Protein Synthesis**: One of the essential functions for all living cells is protein synthesis. For this process, cells require ribosomes.

5. **Ribosomes in Cells**: Ribosomes are the organelles responsible for synthesizing proteins. They are found in both prokaryotic and eukaryotic cells.

6. **Types of Ribosomes**: Ribosomes can be categorized into two types based on their size:
- **70S Ribosomes**: Found in prokaryotic cells.
- **80S Ribosomes**: Found in eukaryotic cells.
The "S" stands for Svedberg unit, which measures the size and density of the ribosomes.

7. **Conclusion**: Since ribosomes are essential for protein synthesis and are present in both prokaryotic and eukaryotic cells, the answer to the question is ribosomes.

**Final Answer**: The cell organelle present in both prokaryotic and eukaryotic cells is ribosomes.

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