There are three basic structures that can be found in most nonbacterial cells. The cell membrane creates the outer boundary of the cell, the nucleus acts as a control center for the cell, and the cytoplasm is the material found between the cell membrane and the nucleus. The first part of this animation shows these basic structures.
The cell membrane surrounds the cell, separates it from its surroundings, and regulates what enters and leaves the cell. The nucleus is the information center of the cell and contains the DNA. It is surrounded by the nuclear envelope, which consists of two membranes. The nucleus also contains the nucleolus, which is made up of RNA and proteins and is responsible for creating ribosomes. The cytoplasm is the area between the nucleus and the cell membrane that acts as protection for the nucleus, creates the shape of the cell, and serves as a buffer.