Ribosomes of bacteria mitochondria and chloroplasts are of

Options

A. 50 S type
B. 80 S type
C. 70 S type
D. 30 S type

Answer

To answer the question regarding the ribosomes of bacteria, mitochondria, and chloroplasts, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Ribosome Structure**:
Ribosomes are cellular structures responsible for protein synthesis. They are composed of ribonucleic acids (RNA) and proteins.

2. **Identify Ribosome Types**:
Ribosomes are categorized based on their sedimentation rates, which are measured in Svedberg units (S). The common types are:
- 30S
- 50S
- 70S
- 80S

3. **Examine Bacterial Ribosomes**:
Bacteria are prokaryotic organisms, and they contain 70S ribosomes. These ribosomes are made up of two subunits: a 50S large subunit and a 30S small subunit.

4. **Analyze Mitochondrial and Chloroplast Ribosomes**:
Mitochondria and chloroplasts are organelles found in eukaryotic cells. They are believed to have originated from ancestral bacteria through endosymbiosis. As a result, they also contain 70S ribosomes, similar to those found in bacteria.

5. **Conclude the Answer**:
Since all three entities (bacteria, mitochondria, and chloroplasts) contain 70S ribosomes, the correct answer to the question is option C: 70S.

### Final Answer:
The ribosomes of bacteria, mitochondria, and chloroplasts are of **70S type** (Option C).

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