nuclear envelope

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envelope

 [en´vĕ-lōp]
1. an encompassing structure or membrane.
2. in virology, the outer lipoprotein coat of a large virus, surrounding the capsid and usually furnished, at least partially, by the host cell. Called also peplos.
3. in bacteriology, the cell wall and the plasma membrane considered together.
nuclear envelope the condensed double layer of lipids and proteins enclosing the cell nucleus and separating it from the cytoplasm; its two concentric membranes, inner and outer, are separated by a perinuclear space.

nu·cle·ar en·ve·lope

the double membrane at the boundary of the nucleoplasm; it has regularly spaced pores covered by a disclike nuclear pore complex and a space or cisterna about 150 Ǻ wide between the two membranes; the outer membrane is continuous at intervals with the rough endoplasmic reticulum.

nuclear envelope

nuclear envelope

a double membrane that surrounds the nucleus of a eukaryotic cell. Also called karyotheca.

nu·cle·ar en·vel·ope

(nū'klē-ăr en'vĕ-lōp)
The double membrane at the boundary of the nucleoplasm; it has regularly spaced pores covered by a disclike nuclear pore complex and a space or cisterna about 150 Å wide between the two layers; the outer membrane is continuous at intervals with the endoplasmic reticulum.
Synonym(s): nuclear membrane.

nuclear envelope

The double membrane, with perforations (pores), surrounding a cell nucleus. The outer membrane extends into the endoplasmic reticulum. The pores allow transport of macromolecules in both directions.

envelope

an encompassing structure or membrane. In virology, a bilayer lipoprotein membrane with glycoprotein spikes surrounding the nucleocapsid and usually furnished, at least partially, by the host cell. In bacteriology, the cell wall and the plasma membrane considered together.

nuclear envelope
the condensed double layer of lipids and proteins enclosing the cell nucleus and separating it from the cytoplasm; its two concentric membranes, inner and outer, are separated by a perinuclear space.