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

CIL:39174*  Cite 

Detail of the origin of the cytopharyngeal microtubules along the left side of the cytopharynx that arise within the filamentous reticulum in contact with its electron-opaque nodes. This system does not arise from the basal bodies of the quadrulus although microtubules do arise along the dorsal edge of the basal bodies of this membranelle and curve between the ends of the cytopharyngeal ribbons and the alveoli of the buccal cavity. The end of the alveoli marks the transition of the buccal cavity into the cytopharynx. As shown on the left of this figure the cytopharyngeal microtubules curve over the cytostomal cord. From here the ribbons fan out into the cytosol. They bind to discoidal vesicles, acidosomes and carrier vesicles and move these vesicles toward the cytopharynx. TEM taken on 3/30/73 by R. Allen with Hitachi HU11A operating at 75kV. Neg. 37,500X.

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 raw negative was scanned with an Epson Perfection V750 Pro and this high resolution image is best used for quantitative analysis. Additional information available at (

Biological Sources
NCBI Organism Classification
Paramecium caudatum
Cell Type
cell by organism
eukaryotic cell
Eukaryotic Protist
Ciliated Protist
Cellular Component
oral apparatus
Biological Context
Biological Process
oral apparatus 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
uranyl salt
osmium tetroxide
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 3450px 0.53nm
Y 3918px 0.53nm