Ribosomes of the cytoplasm, chloroplast and mitochondrion are respectively

Options

A. 80S, 80S and 70S
B. 80S, 70S and 70S
C. 70S in all
D. 80S in all.

Answer

To answer the question regarding the types of ribosomes found in the cytoplasm, chloroplast, and mitochondrion, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Ribosome Types**:
- Ribosomes are essential cellular structures that synthesize proteins. They consist of ribosomal RNA (rRNA) and proteins and are categorized based on their sedimentation rate, measured in Svedberg units (S).

2. **Identifying Ribosome Types in Different Organisms**:
- In prokaryotic cells (like bacteria), ribosomes are typically of the **70S** type, which is composed of a 50S large subunit and a 30S small subunit.
- In eukaryotic cells (like plant and animal cells), ribosomes are generally of the **80S** type, consisting of a 60S large subunit and a 40S small subunit.

3. **Ribosomes in Specific Organelles**:
- **Cytoplasm**: In eukaryotic cells, the ribosomes present in the cytoplasm are of the **80S** type.
- **Chloroplasts**: These organelles, found in plant cells, have ribosomes that are similar to prokaryotic ribosomes, thus they are of the **70S** type.
- **Mitochondria**: Similar to chloroplasts, mitochondria also contain ribosomes that are of the **70S** type.

4. **Compiling the Information**:
- Based on the above information, we can summarize the types of ribosomes as follows:
- **Cytoplasm**: 80S
- **Chloroplast**: 70S
- **Mitochondrion**: 70S

5. **Choosing the Correct Option**:
- The correct answer based on the types of ribosomes in each of these locations is **Option B: 80S, 70S, and 70S**.

### Final Answer:
**Option B: 80S, 70S, and 70S.**

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