The Nucleus is a double membrane bound organelle, responsible for housing DNA. Most cells will only have one nucleus, however some cells (depending on their function) will contain multiple nuclei, such as rat liver cells and skeletal muscle cells or none at all, such as mature red blood cells.

Within the Nucleus is the Nucleolus, this contains RNA and proteins. It is the main site of rRNA synthesis.

The Nuclear membrane contains many holes, called nuclear pores. They are large enough to allow RNA to float in and out of it, but small enough to prevent DNA from escaping.

Notice its location to the Endoplasmic Reticulum. The reason for it being so close to the ER is due to protein synthesis. The Rough ER contains multiple Ribosomes, this stream lines the synthesis of proteins.

For information on Ribosomes click here

For information of Nucleic acids (DNA and RNA) click here

For information on protein Synthesis click here