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

CIL:36221*  Cite 

The bottom of the buccal cavity is surrounded by specialized cytoplasm and contains a lip that constricts the opening leading through the cytostome into the receiving vacuole or nascent vacuole. The oral ribs extend along one side of the cytostome and merge into the cytopharynx. Oral ribs have alveoli between the ribs but alveoli stop at the beginning of the cytopharynx. Lamellae, of 2 microtubules each, border the cytopharynx and direct discoidal vesicles to the site of fusion with the membrane of the growing vacuole. Two electron opaque vesicles, called lysosomes by most authors (eg. Nilsson, Biochem. and Phys. of Protozoa, 2nd ed., Vol 2:339-379, 1979, Acad. Press.), which are probably acidosomes, bind to the nascent vacuole membrane. TEM taken on 8/23/67 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. There is a high resolution version of this image in the library (CIL:39718) which is available for quantitative 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
oral apparatus
primary lysosome
microtubule associated complex
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
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 3824px ——
Y 3096px ——