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

CIL:36667*  Cite 

The body of the trichocyst is composed of a core and a cortex which have slightly different electron diffracting properties, thus the cortex is darker since it scatters more electrons. An electron transparent zone surrounds the cortex and separates the trichocyst membrane from the body. The trichocyst tip is composed of a central spike covered by a sheath. The spike is nail-shaped with its “head” resting on the trichocyst body. The trichocyst membrane completely surrounds both trichocyst body and sheath. (Details of trichocyst fine structure were recorded by Bannister, J. Cell Sci. 11:899-929, 1972.) TEM taken on 4/6/78 by R. Allen with Hitachi HU11A operating at 75kV. Neg. 14,750X. Bar = 0.5µm.

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. The negative was printed to paper and the image was scanned to Photoshop. This digitized image is available for qualitative 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
organelle membrane
Biological Context
Biological Process
organelle organization
organelle membrane organization
Richard Allen (University of Hawaii)
Digital Object Identifier (DOI)
Archival Resource Key (ARK)
Image Type
transmission electron microscopy (TEM)
illumination by electrons
Image Mode
detection of electrons
Parameters Imaged
electron density
Source of Contrast
intrinsic mass distribution
stain with broad specificity
Visualization Methods
stain with broad specificity
uranyl salt
Processing History
recorded image
Print from negative scanned for Photoshop.
Data Qualifiers
processed data
Sample Preparation
glutaraldehyde fixed tissue
tissue in vitreous ice embedment
microtome-sectioned tissue
monoclonal antibody
Relation To Intact Cell
microtome-sectioned tissue
Spatial Axis Image Size Pixel Size
X 1532px ——
Y 1705px ——