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

CIL:10008*  Cite 

Toxicysts in the cytoplasm of cross sectioned non-dividing Didinium. Toxicysts (extrusomes) are multilayered cylinders that are discharged from the cytopharynx region during capture of prey such as Paramecium. Lipid is stored as large non-membrane enclosed dense bodies in the cytosol. TEM taken on 2/18/69 by R. Allen with Philips 300. Neg. 20,500X. Bar = 0.5µm. The negative was printed to paper and the image was scanned to Photoshop. This digitized image is available for qualitative analysis. A raw, unprocessed, high resolution version of this image (CIL:9929) is in the library and available 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
eukaryotic cell
Eukaryotic Protist
Ciliated Protist
Cell Line
Carolina Biological Supply Company, NC, U.S.A.
Cellular Component
rough endoplasmic reticulum
lipid particle
Biological Context
Biological Process
cytoplasm organization
organelle organization
organelle localization
organelle development
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
Print from negative scanned for Photoshop.
Spatial Axis Image Size Pixel Size
X 3732px ——
Y 3032px ——