Nucleus

This article describes an organelle, a cell component with its own distinctive structure and function. In eukaryotic cells, this is bounded by its own membrane, which is a lipid bilayer made of phospholipid.
Unless otherwise specified, information about this organelle is about its in situ occurrence in vivo, i.e., its occurrence in its usual location in living cells.

Definition

The nucleus is an organelle found in eukaryotic cells that performs a lot of coordinating functions related to the cell, including cell compartmentalization, gene expression, and DNA replication.

Summary

Item	Value
Type of organisms whose cells contain a nucleus	Eukaryotic cells only, including plant cells, animal cells, and the cells of protists and fungi.
Type of cells within the organisms that contain a nucleus	Most cells; in particular, any cells that have plans to divide further (i.e., undergo another cell cycle). An exception is mature red blood cells in mammals.