Abstract
Sites of cell proliferation in the ocular apparatus of Aeshna cyanea have been studied by an autoradiographic method ( 3H-thymidine). This technique was used to locate at the compound eye and optic lobe levels the zones of cellular multiplication and the migration of newly formed cells. In addition, the effect of the differential growth of the compound eye on the development of the optical lobe was studied. In the compound eye, two distinct levels of cell proliferation were revealed: the first one was the ocular budding zone itself, i.e. the ocular edge adjacent to the cephalic epidermis. A second mitotic focus, where the cells gather into ommatidial columns, was demonstrated. Thus, two closely related successive mitotic waves occur in the eye of this heterometabolous insect, whereas in holometabolous insects these two phases are much more distinct. Migration of ganglionic cells from the neuroblast masses, where they are formed, to the optical ganglions, where they differentiate, was also followed by this method. In addition, a differential growth of optic lobes was revealed: at the end of the nymphal life, the development was much greater in the posterior area of the optic lobes than in the anterior, although the numbers of cells produced in the neuroblast masses were, at the beginning, identical in both areas. This observation has been interpreted in the light of the experimental results.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
More 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.