Universal cell organelles (found in all living cells) are

Options

A. Ribosomes
B. Plastids
C. Mitochondria
D. Vacuoles

Answer

To determine which of the given options are universal cell organelles found in all living cells, we will analyze each option step by step.

### Step 1: Analyze Ribosomes
- **Ribosomes** are small organelles involved in protein synthesis.
- They are present in both prokaryotic cells (like bacteria) and eukaryotic cells (like plant and animal cells).
- In prokaryotes, ribosomes are of the 70S type, while in eukaryotes, they are of the 80S type.
- Since ribosomes are found in all living cells, they qualify as a universal cell organelle.

### Step 2: Analyze Plastids
- **Plastids** are membrane-bound organelles primarily involved in photosynthesis and storage.
- They are found only in eukaryotic cells, specifically in plants and some protists.
- Prokaryotic cells do not have plastids.
- Therefore, plastids are not universal cell organelles.

### Step 3: Analyze Mitochondria
- **Mitochondria** are known as the powerhouse of the cell, generating energy through cellular respiration.
- Like plastids, mitochondria are also membrane-bound organelles.
- They are present only in eukaryotic cells and are absent in prokaryotic cells.
- Thus, mitochondria are not universal cell organelles.

### Step 4: Analyze Vacuoles
- **Vacuoles** are membrane-bound organelles that store substances and help maintain turgor pressure in plant cells.
- They are primarily found in eukaryotic cells, particularly in plant cells, and are present in some animal cells as well.
- Prokaryotic cells do not have vacuoles.
- Therefore, vacuoles are not universal cell organelles.

### Conclusion
After analyzing all the options, we conclude that the only universal cell organelle found in all living cells is **ribosomes**.

### Final Answer
The correct answer is **Ribosomes**.

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