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:9929*  Cite 

A high resolution image of 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. The raw film was scanned with an Epson Perfection V750 Pro. 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
organelle organization
regulation of organelle organization
Molecular Function
development of organelle
Richard Allen
Digital Object Identifier (DOI)
Archival Resource Key (ARK)
Grouping This image is part of a group.
Spatial Axis Image Size Pixel Size
X 4657px 1nm
Y 3578px 1nm