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

CIL:13105*  Cite 

High resolution image of the cross section through a radial arm of the contractile vacuole complex. The collecting canal occupies the center of the arm whose membrane is supported by the radial microtubular ribbon which has now divided into at least six segments and surrounds the canal. Gaps between the segments are where the mass of membrane tubules of the smooth spongiome opens into the canal. Decorated tubules occurring in bundles form the peripheral layer of the radial arm. TEM taken on 5/2/79 by R. Allen with Hitachi HU11A operating at 75kV. Neg. 18,000X. The raw film was scanned with an Epson Perfection V750 Pro. This image is best used for quantitative analysis. Standard glutaraldehyde fixation followed by osmium tetroxide, dehydrated in alcohol and embedded in an epoxy resin. Microtome sections prepared at approximately 75nm thickness. Additional information available at (

Biological Sources
NCBI Organism Classification
Paramecium multimicronucleatum
Cell Type
cell by organism
eukaryotic cell
Eukaryotic Protist
Ciliated Protist
Cellular Component
contractile vacuole
radial canal of the contractile vacuole complex
microtubule associated complex
Richard Allen (University of Hawaii)
Digital Object Identifier (DOI)
Archival Resource Key (ARK)
Grouping This image is part of a group.
Image Type
transmission electron microscopy (TEM)
illumination by electrons
Image Mode
detection of electrons
Parameters Imaged
electron density
Source of Contrast
stain with broad specificity
Visualization Methods
stain with broad specificity
osmium tetroxide
uranyl salt
lead salt
Processing History
recorded image
unprocessed raw data
Data Qualifiers
raw, unprocessed data
suitable for spatial measurements
Spatial Axis Image Size Pixel Size
X 4600px 0.83nm
Y 5284px 0.83nm