An image of the fibrous cortex of Didinium nasutum. Embedded within the fibrous layer are many extrusive organelles, called mucocysts, involved in cyst formation. In this view there is also a longitudinal section of a more prominent and long curved extrusome (called a cyrtocyst by Wessenberg and Antipa, 1968) in the proter of a dividing cell. The cyrtocyst is of unknown function. Extrusomes of Didinium typically have a bundle of myelin-like membrane material enclosed by their surrounding membrane. This may be stored membrane needed for extrusome discharge. TEM taken on 5/20/69 by R. Allen with a Philips 300 operating at 60kV. Neg. 14,800X. Bar = 0.5?m. The negative was printed to paper and the image was scanned to Photoshop. This digitized image is available for qualitative analysis. A raw, unprocessed, high resolution version of this image (CIL:4665) is in the library and available for quantitative analysis. 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 (http://www5.pbrc.hawaii.edu/allen/).
Biological Process: Cortical organization, Cyst formation, Unknown function
Author: Richard Allen
Source: The Cell: An Image Library