Which is a non-membranous (not covered by membrane) organelle?

Options

A. Ribosome
B. Lysosome
C. Mitochondria
D. Chloroplast

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for a non-membranous organelle, which means we are looking for an organelle that is not surrounded by a membrane.

2. **Reviewing the Options**: The options provided are:
- Ribosome
- Lysosome
- Mitochondria
- Chloroplast

3. **Analyzing Each Option**:
- **Ribosome**: Ribosomes are involved in protein synthesis and are found in both prokaryotic and eukaryotic cells. They are not surrounded by a membrane, making them non-membranous.
- **Lysosome**: Lysosomes are known as the "suicidal bags" of the cell because they contain digestive enzymes. They are membrane-bound organelles, so this option is not correct.
- **Mitochondria**: Mitochondria are known as the powerhouse of the cell and are responsible for energy production. They are also membrane-bound organelles, so this option is not correct.
- **Chloroplast**: Chloroplasts are involved in photosynthesis and are found in plant cells. They are also membrane-bound organelles, so this option is not correct.

4. **Conclusion**: After analyzing all the options, the only organelle that is non-membranous is the **Ribosome**.

### Final Answer:
The non-membranous organelle is **Ribosome**.

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