What is the double membrane surrounding the chromosomes and the nucleolus?

The double membrane surrounding the chromosomes and the nucleolus is known as the nuclear envelope. It consists of two lipid bilayers: an outer membrane that is continuous with the endoplasmic reticulum and an inner membrane that contains proteins specific to the nucleus. The nuclear envelope serves to protect the genetic material within the nucleus and regulates the exchange of substances, such as RNA and proteins, between the nucleus and the cytoplasm through nuclear pores.