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

CIL:9254*  Cite 

This high resolution micrograph may show important features involved in calcareous plate formation within the alveoli that underlie the plasma membrane in Coleps. Densities are seen on the inner alveolar membrane at its corners with septa. These densities are not known at this time in other ciliates and may be involved in calcareous platelet formation within the alveoli or in stabilizing the surface shape. Filamentous material fills the cytosolic space between two densities. Rough endoplasmic reticulum bears prominent ribosomes. Standard glutaraldehyde fixation followed by osmium tetroxide, dehydrated in alcohol and embedded in an epoxy resin. Microtome sections prepared at approximately 75nm thickness. TEM taken on 3/4/69 by R. Allen with Philips 300 operating at 60kV. Neg. 39,900X. The raw film was scanned with an Epson Perfection V750 Pro. This high resolution image is suitable for quantitative analysis. Additional information available at (

Biological Sources
NCBI Organism Classification
Coleps hirtus
Cell Type
eukaryotic cell
Eukaryotic Protist
Ciliated Protist
Cell Line
Cambridge Culture Collection, Cambridge, England, catalog # LB1656/1
Cellular Component
plasma membrane
alveolar membranes
rough endoplasmic reticulum membrane
Biological Context
Biological Process
membrane transport
calcium ion transport
Molecular Function
calcareous plate formation
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 4689px 0.5nm
Y 3624px 0.5nm