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

CIL:36227*  Cite 

Accumulations of acidosome-like vesicles are sometimes found (in this case in a predividing cell) and in this micrograph provide further evidence for invaginations of the outer membranes. It appears to me that these vesicles are more likely multivesicular bodies that have internal vesicles and are known to be late endosomes. When compared to Paramecium these vesicles are equivalent to acidosomes which also have invaginations and are responsible for the transfer of V-type proton pumps to the digestive vacuole. TEM taken on 8/14/67 by R. Allen with Philips 200 operating at 60kV. Neg. 12,400X. Bar = 0.5µm. The negative was printed to paper and the image was scanned to Photoshop. This digitized image is available for qualitative analysis. Additional information available at (

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
phagocytic vesicle
sodium ion-transporting V-type ATPase complex
Biological Context
Biological Process
Molecular Function
Richard Allen (University of Hawaii)
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
Print from negative scanned for Photoshop.
Data Qualifiers
processed data
Spatial Axis Image Size Pixel Size
X 3093px ——
Y 2566px ——