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

CIL:4666*  Cite 

High resolution image of one of several contractile vacuole pores of the proter of a dividing cell. This is presumably at an early stage of development as division is not yet complete. This section shows the pore to be encased in microtubules. The micrograph shows the microtubules cut transversely on one side so one can count them and obliquely on the other side of the pore. Whether the CV is yet functional at this stage is not known although the pore septum appears as two flaps of membrane. The pore lies close to the division furrow in the proter. TEM taken on 5/21/69 by M. Sage with Philips 300 operating at 60kV. Neg. 14,800X. The raw film was scanned with a Nikon Coolscan 9000ED. This image is suitable 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
Didinium nasutum
Cell Type
cell by organism
eukaryotic cell
Eukaryotic Protist
Ciliated Protist
Cell Line
Carolina Biological Supply Company, NC, U.S.A.
Cellular Component
contractile vacuole pore
cell cortex
cell cortex part
Biological Context
Biological Process
water transport
development of contractile vacuole pore
M. Sage
Richard Allen
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 5516px 1nm
Y 3726px 1nm