What is nucleolus? Explain its function.

Explanation

### Step-by-Step Solution:

1. **Definition of Nucleolus**:
The nucleolus is a small, dense structure located within the nucleus of eukaryotic cells. It is not surrounded by a membrane and is composed of RNA, DNA, and proteins.

2. **Discovery of Nucleolus**:
The nucleolus was discovered by the scientist Fontana in the year 1774. This historical context adds to our understanding of its significance in cell biology.

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