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

CIL:21728*  Cite 

Quick-freeze deep-etch view of a radial arm showing a collecting canal surrounded with smooth spongiome as well as a few decorated tubules. However several larger vesicles lie next to the radial arm containing a lumen resembling the contractile vacuole. These vesicles appear to be rounded decorated tubules which have been transformed into vesicles or have not yet tubulated and become part of the decorated spongiome of the mature radial canal. Although we cannot be certain without further study we believe this may represent a dividing cell as we do know that the radial arms of the dividing cell, both their smooth and decorated spongiomes, shorten as the new CVCs develop (Allen et al., J. Cell Sci. 96:469-475, 1990; Fok et al., J. Eukaryot. Microbiol. 49:185-196, 2002. The P-face of these vesicles has a large number of IMPs like that seen in collecting canals. The highly porous E-face of several vesicles indicates that these vesicles are indeed products of the decorated spongiome. TEM taken on 6/22/88 by C. Schroeder with Zeiss 10A operating at 80kV. Neg. 9,780X. Bar = 0.5µm. A print of the negative was scanned and processed in Photoshop. This image is best used for qualitative analysis. A high resolution image (CIL:13130) is available for quantitative analysis. 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
integral to contractile vacuolar membrane
Biological Context
Biological Process
contractile vacuole organization
Richard Allen (University of Hawaii)
C. Schroeder
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
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 1758px ——
Y 1902px ——