Nucleus

The nucleus is a membrane-bound organelle found in eukaryotic cells. It contains the cell's genetic material and is responsible for controlling the cell's activities.

Structure of the Nucleus

• Nuclear Envelope: A double membrane that surrounds the nucleus, separating it from the cytoplasm.
• Nuclear Pores: Openings in the nuclear envelope that allow for the exchange of materials between the nucleus and the cytoplasm.
• Nucleoplasm: The semi-fluid substance within the nucleus where the genetic material and nucleolus are found.
• Chromatin: The complex of DNA and proteins that makes up the genetic material of the nucleus.
• Nucleolus: A small, dense region within the nucleus where ribosomal RNA (rRNA) is synthesized.

Functions of the Nucleus

The nucleus has several important functions:

1. Control of Gene Expression: The nucleus regulates the expression of genes, determining which proteins are produced in the cell.
2. Storage and Protection of Genetic Material: The genetic material (DNA) is stored within the nucleus and protected from damage by the nuclear envelope.
3. Ribosome Synthesis: The nucleolus is involved in the synthesis of ribosomal RNA, which is essential for the production of ribosomes.
4. Cell Reproduction: The nucleus plays a key role in cell division, ensuring that each daughter cell receives the correct amount of genetic material.

Study Guide

Here are some key points to remember about the nucleus:

1. What is the structure of the nucleus?
2. What are the functions of the nucleus?
3. How does the nucleus control gene expression?
4. What is the role of the nucleolus?
5. How does the nucleus contribute to cell reproduction?

Remember to review the structure and functions of the nucleus to ensure a thorough understanding of this important cell organelle.