Describe the role of the nuclear envelope.

The nuclear envelope plays a crucial role in maintaining the integrity and functionality of the nucleus within a eukaryotic cell. Specifically, it serves as a double-layered membrane that separates the contents of the nucleus from the cytoplasm. This separation is vital because it creates a distinct environment in which the processes of transcription and DNA replication can occur without interference from the activities taking place in the cytoplasm.

Additionally, the nuclear envelope is equipped with nuclear pores that function as gateways, regulating the passage of materials, such as RNA and proteins, between the nucleus and the cytoplasm. This selective transport is crucial for the cell's overall functioning, as it ensures that only the necessary components can enter or leave the nucleus, thus maintaining the nucleus's specialized role in the cell.

While options related to structural support, separation of the nucleolus from the cytoplasm, or production of ribosomes touch on aspects of cell biology, they do not accurately capture the fundamental and defining function of the nuclear envelope. The correct answer highlights its vital role as a barrier and regulatory structure, which is essential for maintaining cellular organization and function.