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

CIL:36769*  Cite 

The cytosol of Paramecium contains many vesicles of various sizes, shapes and contents as well as complex particles such as ribosomes and glycogen granules. The rough endoplasmic reticulum exists as membrane cisternae and tubules which bear ribosomes on their cytosolic surface. Mitochondria and peroxisomes both have tubular membrane inclusions. Large vesicles with an electron transparent center are acidosomes. Lysosomes have a heterogeneous content but always have a heavy polysaccharide lining on their luminal membrane face. Flattened vesicles, called discoidal vesicles, form a pool of membrane from which phagosome membrane is derived. TEM taken on 10/30/68 by R. Allen with Philips 300 operating at 60kV. Neg. 20,500X. Bar = 0.5µm.

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 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:39140) which is available 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
vesicle membrane
Biological Context
Biological Process
cytoplasm 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
lead salt
osmium tetroxide
Processing History
recorded image
Print from negative scanned for Photoshop.
Data Qualifiers
processed data
Spatial Axis Image Size Pixel Size
X 3000px ——
Y 3472px ——