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

CIL:25687*  Cite 

Cytoplasm of a green Trichodina that lives on the surface of a freshwater snail collected in central Illinois. In this view the abundant endosymbiotic zoochlorellae and a single endosymbiotic bacterium are evident. The bacterial endosymbiont is filled with virion particles. In this image the particles can also be seen loose in the cytoplasm of Trichodina. See serial section CIL:25688). TEM taken by G. Antipa in 1968 on a Hitachi HU11A operating at 75kV. The negative magnification is 11,500X. The raw film was scanned with an Epson Perfection V750 Pro. This image is best used for quantitative analysis. Standard glutaraldehyde fixation followed by osmium tetroxide, dehydrated in alcohol and embedded in an epoxy resin. Microtome sections prepared at approximately 65nm thickness.

Biological Sources
NCBI Organism Classification
Cell Type
cell by organism
eukaryotic cell
Eukaryotic Protist
Ciliated Protist
Cellular Component
symbiont-containing vacuole
symbiont-containing vacuole
bacterial symbiont
chloroplast thylakoid
chloroplast thylakoid membrane
Biological Context
Biological Process
response to symbiont
oral apparatus organization
cytoplasm organization
eukaryotic photosynthetic symbiont
bacterial endosymbiont
viral particles within a bacterial symbiont
chloroplast organization
Gregory Antipa (San Francisco State University)
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 5304px 1.3nm
Y 5252px 1.3nm