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

CIL:36736*  Cite 

In order to study all stages of DVs in the same cell we used a protocol of sequentially exposing cells to different sizes of latex beads interspersed with washes: for example, 3 minutes in 0.1µm beads, wash 3 min, 3 minutes in 0.3µm beads, wash 3 min, 3 minutes in 0.6µm beads, wash 3 min, 3 minutes in 0.8µm beads, wash 3 min and finally 3 minutes in 1.1µm beads followed by fixing the cells. Thus the 1.1, 0.8, 0.6, 0.3 and 0.1µm bead-containing vacuoles will be 0-3 min, 6-9 min, 12-15 min, 18-21 min and 24-27 minutes old, respectively. The electron micrograph shown here was of a DV-II that was surrounded with docked secondary lysosomes. Secondary lysosomes only recognize and dock at the DV-II membrane. They do not dock with DV-I or DV-III vacuoles. TEM taken on 2/27/81 by R. Allen with Hitachi HU11A operating at 75kV. Neg. 7,000X. 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. Additional information available at (

Biological Sources
NCBI Organism Classification
Paramecium multimicronucleatum
Cell Type
cell by organism
eukaryotic cell
Eukaryotic Protist
Ciliated Protist
Cellular Component
food vacuole
secondary lysosome
Biological Context
Biological Process
digestive system process
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 2324px ——
Y 3000px ——