Site of formation of ribosomal precursor/ribosomal subunits in cell is

Options

A. nucleus
B. nucleolus
C. Golgi body
D. stroma

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the site of formation of ribosomal precursors or ribosomal subunits in a cell.

2. **Identifying the Options**: The options provided are:
- A) Nucleus
- B) Nucleolus
- C) Golgi Body
- D) Stroma

3. **Analyzing Each Option**:
- **Nucleus**: While the nucleus is the control center of the cell and contains genetic material, it is not the specific site for ribosomal subunit formation.
- **Nucleolus**: The nucleolus is a dense, rounded structure within the nucleus and is specifically known for synthesizing ribosomal RNA (rRNA) and assembling ribosomal subunits. It is often referred to as the "factory of ribosomes."
- **Golgi Body**: The Golgi body is primarily involved in the modification, sorting, and secretion of proteins and lipids, not in the formation of ribosomal subunits.
- **Stroma**: The stroma refers to the fluid-filled space in chloroplasts where the dark reactions of photosynthesis occur, and it is not related to ribosome formation.

4. **Conclusion**: Based on the analysis, the correct answer is **B) Nucleolus**, as it is the site where ribosomal precursors and subunits are formed.

5. **Final Answer**: The site of formation of ribosomal precursor/ribosomal subunits in the cell is the **nucleolus**.

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