Which of the following is described as cell within the cell or prokaryotic cell within a eukaryotic cell?

Options

A. Nucleus
B. Ribosome
C. Mitochondria
D. Endoplasmic Reticulum

Answer

To solve the question "Which of the following is described as cell within the cell or prokaryotic cell within a eukaryotic cell?", we will analyze the options provided and identify the correct answer step by step.

### Step 1: Understand the Question
The question is asking for an organelle that can be described as a "cell within a cell" or a "prokaryotic cell within a eukaryotic cell." This implies that the organelle should have characteristics similar to prokaryotic cells, such as having its own DNA and the ability to perform some functions independently.

### Step 2: Analyze the Options
The options given are:
1. Nucleus
2. Ribosome
3. Mitochondria
4. Endoplasmic Reticulum

### Step 3: Evaluate Each Option
- **Nucleus**: The nucleus is the control center of the cell and contains the cell's genetic material (DNA). However, it does not fit the description of a prokaryotic cell within a eukaryotic cell.

- **Ribosome**: Ribosomes are the sites of protein synthesis in the cell. They do not have their own DNA and are not considered cells.

- **Mitochondria**: Mitochondria are known as the powerhouse of the cell. They have their own circular DNA and ribosomes, similar to prokaryotic cells. They can replicate independently of the cell, which aligns with the description of being a "cell within a cell."

- **Endoplasmic Reticulum**: The endoplasmic reticulum is involved in protein and lipid synthesis but does not have its own DNA and is not considered a cell.

### Step 4: Identify the Correct Answer
Based on the analysis, the only organelle that fits the description of being a "cell within a cell" or a "prokaryotic cell within a eukaryotic cell" is **Mitochondria**.

### Final Answer
The correct answer is **C. Mitochondria**.

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