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

CIL:34746*  Cite 

The oral apparatus of Tetrahymena. The undulating membrane is composed of two rows of basal bodies but only the outer row is ciliated. Both basal bodies are fully formed but only the ciliated member has an axosome and 9 + 2 axoneme. The oral ribs each contain two microtubular ribbons of 4 and 2 microtubules respectively and alveoli lie between. TEM taken on 8/25/67 by R. Allen with Philips 200 operating at 60kV. Neg. 2,400X. The raw film was scanned with an Epson Perfection V750 Pro. This image is best used for quantitative analysis.

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. Additional information available at (

Biological Sources
NCBI Organism Classification
Tetrahymena pyriformis
Cell Type
cell by organism
eukaryotic cell
Eukaryotic Protist
Ciliated Protist
Cellular Component
oral apparatus
axonemal microtubule
microtubule basal body
cortical microtubule
Biological Context
Biological Process
oral apparatus organization
microtubule basal body organization
ciliary axoneme organization
Richard Allen (University of Hawaii)
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 4900px 6.2nm
Y 6083px 6.2nm