If A 70S ribosomes, B - 80S ribosomes, C -single circular DNA, D -RNA molecules, E -double helical DNA, F - thylakoids and G - stromal lamellae, which of the following set is found in mitochondria?

Options

A. B, D, E, F
B. D, E, F,G
C. A. D, E
D. A, C, D

Answer

To determine which structures are found in mitochondria from the given options, we can analyze each one step by step:

1. **70S Ribosomes (A)**: Mitochondria contain 70S ribosomes, which are similar to those found in prokaryotes. This allows them to synthesize some of their own proteins independently of the nuclear DNA. Therefore, this option is correct.

2. **80S Ribosomes (B)**: 80S ribosomes are typically found in eukaryotic cytoplasm and are not present in mitochondria. Hence, this option is incorrect.

3. **Single Circular DNA (C)**: Mitochondria possess their own DNA, which is circular in shape, similar to bacterial DNA. This allows mitochondria to replicate independently of the cell's nuclear DNA. Thus, this option is correct.

4. **RNA Molecules (D)**: Mitochondria can transcribe their circular DNA into RNA molecules. Therefore, this option is also correct.

5. **Double Helical DNA (E)**: Mitochondria do not contain double helical DNA; they have circular DNA. Thus, this option is incorrect.

6. **Thylakoids (F)**: Thylakoids are structures found in chloroplasts, not mitochondria. Therefore, this option is incorrect.

7. **Stromal Lamellae (G)**: Stromal lamellae are also found in chloroplasts and are not present in mitochondria. Hence, this option is incorrect.

**Conclusion**: The structures found in mitochondria are A (70S ribosomes), C (single circular DNA), and D (RNA molecules).

### Final Answer:
The correct set of structures found in mitochondria is A (70S ribosomes), C (single circular DNA), and D (RNA molecules).