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*CIL – Cell Image Library accession number. Please use this to reference an image.

CIL:36648*  Cite 

A freeze-fractured view of the nuclear envelope. The fracture in the middle of the figure exposes the cytosolic facing membrane. This can be distinguished by a fractured cytoplasmic organelle at the top of the picture. The lower part of the picture shows the nucleoplasm-facing membrane of the envelope. The nuclear pores penetrate through both membranes. It is not clear if the membranes have actually fractured along their hydrophobic centers or if the true surfaces of these two membranes are being viewed. TEM taken on 2/16/76 by R. Allen with Hitachi HU11A operating at 75kV. Neg. 14,579X. Bar = 0.25µm.

Biological Sources
NCBI Organism Classification
Paramecium multimicronucleatum
Cell Type
cell by organism
eukaryotic cell
Eukaryotic Protist
Ciliated Protist
Cellular Component
nuclear pore
nuclear membrane
Biological Context
Biological Process
nuclear pore distribution
nuclear membrane organization
Richard Allen (University of Hawaii)
Digital Object Identifier (DOI)
Archival Resource Key (ARK)
Image Type
transmission electron microscopy (TEM)
illumination by electrons
Image Mode
electron density
Parameters Imaged
elastic scattering of electrons
electron density
Source of Contrast
differences in deposition of metal shadow
Visualization Methods
transmission electron microscopy (TEM)
Processing History
shadowing and plating
recorded image
Print of negative scanned for Photoshop
Data Qualifiers
processed data
Spatial Axis Image Size Pixel Size
X 2323px ——
Y 3000px ——