Alternate header for print version

Public Domain: This image is in the public domain and thus free of any copyright restrictions. However, as is the norm in scientific publishing and as a matter of courtesy, any user should credit the content provider for any public or private use of this image whenever possible. Learn more
*CIL – Cell Image Library accession number. Please use this to reference an image.

CIL:36234*  Cite 

A partially filled contractile vacuole is connected to two regions of spongiome tubules. The extra CV membrane is acquired from these spongiomes. Presumably some of these spongiome tubules are decorated with pegs which in Paramecium are known to be V-type proton pumps. A spent vacuole lies nearby and has a filamentous area in which membrane tubulation and vesiculation is taking place. A similar filamentous array does not appear to be present in the spongiome region of the CV or along the CV membrane itself. TEM taken on 4/21/78 by R. Allen with Hitachi HU11A operating at 60kV. Neg. 9,200X. Bar = 0.5µm. The negative was printed to paper and the image was scanned to Photoshop. This digitized image is available for qualitative analysis. There is a high resolution version of this image in the library (CIL:39799) which is available for quantitative analysis. Additional information available at (

Technical Details

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 Context
Biological Process
contractile vacuole organization
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
Print from negative scanned for Photoshop.
Data Qualifiers
processed data
Spatial Axis Image Size Pixel Size
X 3445px ——
Y 3184px ——