The inner membrane has what relationship to the outer membrane and NPCs?

The inner membrane has what relationship to the outer membrane and NPCs?

• A. It is continuous with the outer membrane at the nuclear pore complexes
• B. It is identical to the outer membrane
• C. It is not attached to NPCs
• D. It is separated from the nuclear material by the lamina

Answer: (A)

Two lipid bilayers form the nuclear envelope, and nuclear pore complexes span both of them. At these pores, the inner and outer membranes are connected, so they are continuous through the pore. This means the inner membrane is continuous with the outer membrane specifically at the nuclear pore complexes. The outer membrane is also continuous with the endoplasmic reticulum, and the space between the two membranes (the perinuclear space) communicates with the ER lumen. The lamina lies on the inner surface of the inner membrane, providing structural support and interacting with chromatin, rather than acting as a barrier between the nucleus and its contents.

Two lipid bilayers form the nuclear envelope, and nuclear pore complexes span both of them. At these pores, the inner and outer membranes are connected, so they are continuous through the pore. This means the inner membrane is continuous with the outer membrane specifically at the nuclear pore complexes. The outer membrane is also continuous with the endoplasmic reticulum, and the space between the two membranes (the perinuclear space) communicates with the ER lumen. The lamina lies on the inner surface of the inner membrane, providing structural support and interacting with chromatin, rather than acting as a barrier between the nucleus and its contents.