Which component is present in a prokaryotic cell?

Options

A. ER
B. Chloroplasts
C. Ribosomes
D. Mitochondria

Explanation

**Step-by-Step Solution:**

1. **Identify the Types of Cells**: Understand that there are two main types of cells: prokaryotic and eukaryotic. Prokaryotic cells are unicellular organisms that lack membrane-bound organelles.

2. **List the Components**: The question lists several components: Endoplasmic Reticulum (ER), chloroplast, ribosome, and mitochondria.

3. **Determine Membrane-Bound Organelles**: Recognize that prokaryotic cells do not contain membrane-bound organelles. Membrane-bound organelles include ER, mitochondria, lysosomes, and chloroplasts.

4. **Analyze Each Component**:
- **Endoplasmic Reticulum (ER)**: This is a membrane-bound organelle found in eukaryotic cells, not in prokaryotic cells.
- **Chloroplast**: This is also a membrane-bound organelle, primarily found in plant cells (eukaryotic), and is absent in prokaryotic cells.
- **Mitochondria**: Another membrane-bound organelle, found in eukaryotic cells, not in prokaryotic cells.
- **Ribosome**: This is not a membrane-bound organelle and is present in both prokaryotic and eukaryotic cells.

5. **Conclusion**: The only component present in a prokaryotic cell from the given options is the ribosome.

**Final Answer**: Ribosome is the component present in a prokaryotic cell.

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