Non membranous cell organelles are

Options

A. mitochondria
B. ribosomes
C. ER and nucleolus
D. ribosomes and centrioles

Answer

**Step-by-Step Solution:**

1. **Understanding Non-Membranous Organelles**: Non-membranous organelles are cell structures that do not have a surrounding membrane. This distinguishes them from membranous organelles, which are enclosed by lipid membranes.

2. **Analyzing the Options**:
- **Option 1: Mitochondria**: Mitochondria are membrane-bound organelles, specifically double-membranous, involved in ATP production. Therefore, they are not non-membranous.
- **Option 2: Ribosomes**: Ribosomes are indeed non-membranous organelles. They are responsible for protein synthesis and do not have a membrane.
- **Option 3: Endoplasmic Reticulum and Nucleus**: Both the endoplasmic reticulum and the nucleus are membrane-bound organelles. The endoplasmic reticulum is involved in protein and lipid synthesis, while the nucleus houses genetic material.
- **Option 4: Ribosomes and Centrioles**: Ribosomes are non-membranous, and centrioles are also non-membranous structures found in animal cells. Centrioles play a key role in cell division.

3. **Identifying the Correct Answer**: Based on the analysis, the correct answer is **Option 4: Ribosomes and Centrioles**, as both are non-membranous organelles.

4. **Conclusion**: The non-membranous cell organelles are ribosomes and centrioles.

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