Abstract
During postembryonic development, the ventral glands of Ephemera danica increase in size until the last nymphal instar, and start to diminish prior to the subimaginal moult. The ultrastructural examination demonstrates that degeneration of the glands is initiated by the release of cytoplasm from the gland cells. In the subimagines, these cells contain only small amounts of remaining cytoplasm and a few mitochondria, but increasing numbers of lysosome-like bodies. The nuclear chromatin is condensed. Spherical, pycnotic nuclei are the main characteristics of imaginal glands. In the earliest stages investigated, the formation of large vesicles of the endoplasmic reticulum and their release into the glandular cavity were observed, indicating secretion. In the gland cells of early last nymphal instars, the large number of mitochondria and tubules of the agranular endoplasmic reticulum suggests a high rate of hormone production. The only sexual variation observed in the ventral glands of the stages studied was their larger size in the females.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: International Journal of Insect Morphology and Embryology
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
