This is known as the nuclear membrane or the nuclear envelope. So, just like the entire eukaryotic cell contains our cell membrane, the nucleus contains a membrane known as the nuclear membrane. And the nuclear membrane, just like the actual cell membrane, also consists of a lipid bilayer. So we have an inner as well as an outer region of the membrane that basically looks something like this. So we have the outer membrane region that consists of the hydrophilic heads and the hydrophobic tails. And we have the inner membrane region that also consists of our hydrophilic heads and the hydrophobic tails.