The stroma of the chloroplast contains

Options

A. Enzymes required for protein synthesis
B. Enzymes required for carbohydrate synthesis
C. Double stranded circular DNA molecules and ribosomes (70S)
D. Allof the above

Answer

To answer the question about what the stroma of the chloroplast contains, we can break it down step by step:

### Step-by-Step Solution:

1. **Understanding the Stroma**: The stroma is the fluid-filled space inside the chloroplast, surrounding the thylakoids. It plays a crucial role in the process of photosynthesis.

2. **Components of the Stroma**:
- **Enzymes for Protein Synthesis**: The stroma contains enzymes that are essential for synthesizing proteins. These proteins are vital for various cellular functions, including energy metabolism.

- **Enzymes for Carbohydrate Synthesis**: The stroma also contains enzymes necessary for the synthesis of carbohydrates. This is part of the Calvin cycle, where carbon dioxide and water are converted into glucose.

- **Double-Stranded Circular DNA**: Chloroplasts have their own DNA, which is circular and double-stranded. This DNA carries the genetic information necessary for the functioning and replication of the chloroplast.

- **Ribosomes**: The stroma contains ribosomes, which are the sites of protein synthesis. These ribosomes are similar to those found in prokaryotic cells, reflecting the endosymbiotic origin of chloroplasts.

3. **Conclusion**: Since the stroma contains all of the above components—enzymes for protein synthesis, enzymes for carbohydrate synthesis, double-stranded circular DNA, and ribosomes—the correct answer to the question is "all of the above."

### Final Answer:
The stroma of the chloroplast contains enzymes required for protein synthesis, enzymes required for carbohydrate synthesis, double-stranded circular DNA, and ribosomes. Therefore, the answer is "all of the above."

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