If living cells, similar to those found on earth, were found on another planet, where there was no oxygen, which cell organelle would most probably be absent ?

Options

A. Ribosomes
B. Golgi apparatus
C. Mitochondria
D. Endoplasmic Reticulum

Answer

To answer the question of which cell organelle would most probably be absent in living cells found on another planet where there is no oxygen, we can analyze each option provided:

### Step-by-Step Solution:

1. **Understanding the Context**:
- The question asks about living cells similar to those on Earth but in an environment devoid of oxygen. We need to identify which organelle relies on oxygen for its function.

2. **Analyzing Each Organelle**:
- **Ribosomes**:
- Function: Ribosomes are the sites of protein synthesis.
- Oxygen Requirement: They do not require oxygen to synthesize proteins.
- Conclusion: Ribosomes would likely be present.

- **Golgi Apparatus**:
- Function: The Golgi apparatus is involved in the modification and packaging of proteins.
- Oxygen Requirement: It does not require oxygen for its functions.
- Conclusion: The Golgi apparatus would likely be present.

- **Mitochondria**:
- Function: Mitochondria are known as the powerhouse of the cell, generating ATP through aerobic respiration.
- Oxygen Requirement: They require oxygen to produce ATP efficiently.
- Conclusion: In the absence of oxygen, mitochondria would not function properly and would likely be absent.

- **Endoplasmic Reticulum (ER)**:
- Function: The ER is involved in the synthesis of lipids and proteins.
- Oxygen Requirement: The ER can function without oxygen.
- Conclusion: The endoplasmic reticulum would likely be present.

3. **Final Conclusion**:
- Based on the analysis, the organelle that would most probably be absent in cells on a planet without oxygen is **Mitochondria**.

### Answer:
**C. Mitochondria**

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