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

CIL:25691*  Cite 

A view of the cytoplasm of a green Trichodina that lives on the surface of a freshwater snail collected in central Illinois. In this view the 10 endosymbiotic bacteria are evident as well as an endosymbiotic zoochlorella. The endosymbiotic bacteria are full of viral particles and a few can be seen in the cytoplasm. A large food vacuole is present and oral membranelles are evident. Other features of the oral apparatus such as microtubules aligning the walls and a noded system at one side are exhibited. Additionaly, the macronuclear organization is observed. TEM taken by G. Antipa in 1968 on a Hitachi HU11A operating at 75kV. The negative magnification is 5,000X. 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
bacterial endosymbiont
oral apparatus
food vacuole
microtubule associated complex
noded fiber
Biological Context
Biological Process
response to symbiont
oral apparatus organization
cytoplasm organization
eukaryotic photosynthetic symbiont
prokaryotic symbiont
virion transport
macronucleus organization
Gregory Antipa (San Francisco State University)
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
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
Spatial Axis Image Size Pixel Size
X 5450px 2.8nm
Y 5423px 2.8nm