Mitochondrion is semiautonous cell organelle due to the presence of

Options

A. 70S Ribosomes
B. Circular DNA
C. Cell wall
D. Plasma membrane

Answer

### Step-by-Step Solution:

1. **Understanding the Term "Semi-autonomous":**
- Semi-autonomous organelles are those that can perform some functions independently but still rely on the cell's nucleus for certain aspects of their operation.

2. **Identifying the Features of Mitochondria:**
- Mitochondria are known as the powerhouses of the cell, responsible for producing energy in the form of ATP.
- They contain their own genetic material, which is crucial for their function.

3. **Analyzing the Options:**
- **Option 1: 70S Ribosomes** - While mitochondria do contain 70S ribosomes, this feature alone does not define them as semi-autonomous.
- **Option 2: Circular DNA** - Mitochondria possess circular DNA similar to prokaryotes, allowing them to synthesize some of their own proteins and enzymes.
- **Option 3: Cell Wall** - Mitochondria do not have a cell wall; this option is incorrect.
- **Option 4: Plasma Membrane** - While mitochondria have a plasma membrane, this does not contribute to their semi-autonomous nature.

4. **Conclusion:**
- The presence of circular DNA in mitochondria is the key reason they are classified as semi-autonomous organelles. This DNA allows them to produce some of their own proteins and enzymes, although they still depend on the nuclear DNA for many others.

### Final Answer:
Mitochondrion is a semi-autonomous cell organelle due to the presence of **circular DNA**.