In eukaryotic cells like those present in animals and human beings, the nucleus is the most prominent and important organelle. It is typically rounded or oval in shape and situated somewhere at the center of the cell. The nucleus in animal cells for example is responsible for various essential processes like gene expression and DNA replication. Through the cell’s nucleus, cells are able to go into mitosis for multiplication and proliferation. Without the cell nucleus directing these processes, cells will be unable to undergo growth and development.
In the case of animal and human cells, hereditary traits are replicated and transferred to other cells because of the nucleus. Through gene expression, new cells will be born with basically a copy of the genetic contents of the parent cell. When cells multiply, it actually starts with a process called cell division wherein one parent cell may become two daughter cells. Each of these daughter cells will have the same set of contents including the genetic traits encoded in the cell DNA. Through the cell nucleus, this activity is regulated and supported. For human reproductive cells, the nucleus will be the main organelle that will support DNA replication of the daughter cells that will be created by cell division. The product of such process will become a baby with basically the same traits as that of the parent cell.
The term nucleus may also be applied to the core component of atoms and particles. Most of the atomic weight of a particular substance is attributed to its nucleus which is surrounded by other particles in the form of protons and electrons. Different substances or particles have different arrangements of their protons and electrons but all surround the core component which is called the nucleus. This idea of the nucleus is being the center or core component is also commonly applied to some basic occurrences in life. A centralized office or command station for emergency and police services for example is considered the nucleus of the whole operation.