The part of the cell that contains genetic material is the nucleus. The nucleus serves as the control center for cellular activities, housing the cell’s DNA, which contains the instructions for growth, development, and reproduction. It is surrounded by a double membrane known as the nuclear envelope, which protects the DNA and regulates the exchange of materials between the nucleus and the cytoplasm. The study of the nucleus is crucial in understanding genetics, cell function, and the processes of replication and gene expression.