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

CIL:36223*  Cite 

The nascent digestive vacuole forms as the membrane of flattened vesicles fuse with the single membrane of the cytopharynx between the lamellae (2 microtubules forming a lamella) that are connected along their length to the membrane at the cytopharynx. Another portion of the forming vacuole is associated with the ends of the 4 element- (4 mt) and 2 element- (2 mt) microtubular ribbons that come from the oral ribs. These ribbons are covered with specialized cytoplasm and do not take part in moving discoidal vesicles to the vesicle fusion region. One feature of the nascent vacuole in Tetrahymena that has not been observed in Paramecium is the presence of coated pits extending from the vacuole membrane. Finally, vesicles previously called lysosomes, which to me resemble the late endosomes, acidosomes, of Paramecium, dock at the growing vacuole. For a review of the literature of phagocytosis in Tetrahymena see Nilsson, Biochemistry and Physiology of Protozoa, 2nd ed., Academic Press, pp. 339-379, 1979; Sattler and Staehelin, J. Ultrastructure Res. 66:132-150, 1979; and Baumert et al., Eur. J. Protistol. 34:291-300, 1998. TEM taken on 8/15/67 by R. Allen with Philips 200 operating at 60kV. Neg 19,200X. 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:39720) 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
phagocytic vesicle
phagocytic vesicle membrane
microtubule associated complex
Biological Context
Biological Process
phagocytosis, engulfment
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 3069px ——
Y 3760px ——