Ribosomes is an organelle observed in a eukaryotic cell involved in protein synthesis . Ribosomes of a eukaryotic is 80S type . It is associated with which of these ?
I. Plasmid
II. Mitochondrion
III. Nucleus
IV. Golgi Body
V.Endosplasmic Reticulum

Options

A. I, II, III and IV
B. I, II and III only
C. I and II only
D. III and V only

Answer

To solve the question regarding the association of 80S ribosomes in a eukaryotic cell, we will analyze each option provided.

### Step-by-Step Solution:

1. **Understanding Ribosomes**:
- Ribosomes are cellular structures responsible for protein synthesis. In eukaryotic cells, the ribosomes are of the 80S type, which is larger than the 70S ribosomes found in prokaryotic cells.

2. **Analyzing Each Option**:
- **I. Plasmid**: Plasmids are extrachromosomal DNA found in prokaryotes. They do not contain ribosomes. Thus, this option is incorrect.
- **II. Mitochondrion**: Mitochondria are semi-autonomous organelles that contain their own ribosomes, which are of the 70S type, not 80S. Therefore, this option is also incorrect.
- **III. Nucleus**: The nucleus is a membrane-bound organelle found in eukaryotic cells that contains the cell's genetic material. It does not contain ribosomes directly, but it is associated with the synthesis of ribosomal RNA (rRNA). This option is correct in the context of eukaryotic cells.
- **IV. Golgi Body**: The Golgi apparatus is involved in modifying, sorting, and packaging proteins. It does not contain ribosomes, so this option is incorrect.
- **V. Endoplasmic Reticulum (ER)**: The rough endoplasmic reticulum (RER) has ribosomes attached to its surface, which are indeed 80S ribosomes. Thus, this option is correct.

3. **Conclusion**:
- The correct associations of 80S ribosomes in a eukaryotic cell are with the **Nucleus (III)** and the **Endoplasmic Reticulum (V)**. Therefore, the answer is options **III and V**.

### Final Answer:
The 80S ribosomes in a eukaryotic cell are associated with the **Nucleus (III)** and the **Endoplasmic Reticulum (V)**.

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