Nucleus
The function of the nucleus is to control the activities of a cell through regulating gene expression. These cell activities include metabolism, growth, and reproduction. It also stores and protects the cell's DNA. The nucleus sends information, receives information, and keeps the cell balanced. The nucleus is the "brain" of cell, so you can see why it is important. It holds the DNA and controls most processes throughout the cell. When the cell splits, the DNA replicates in the nucleus.