🔬general biology i review

Nuclear envelope

Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025

Definition

The nuclear envelope is a double-membrane structure that encloses the nucleus, separating it from the cytoplasm. It functions to protect the genetic material and regulate the flow of molecules in and out of the nucleus.

5 Must Know Facts For Your Next Test

  1. The nuclear envelope consists of two lipid bilayers: an outer membrane and an inner membrane.
  2. Nuclear pores are embedded in the nuclear envelope, allowing selective exchange of substances between the nucleus and cytoplasm.
  3. The outer membrane of the nuclear envelope is continuous with the endoplasmic reticulum.
  4. The nuclear lamina, a dense network of proteins, provides structural support to the nuclear envelope from its inner side.
  5. During mitosis, the nuclear envelope disassembles and reassembles to allow chromosome segregation.

Review Questions

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