Contents of this webseries on Embryology
In these webpages original material of the Radboud University Nijmegen (© copyrights) is shown on the descriptive embryology in animals (more
. There are photographs are presented as well as drawings, movies and posters (meer
...) of microscopical sections and in toto
(= whole mount) preparations of the early embryology in the following animal species/groups:
- The Sea urchin (Echinoidea)
- The Amphibians (frog Rana esculenta/Pelophylax and tadpole, Xenopus laevis)
- The Chicken (Gallus gallus domesticus)
- The Mouse ((Mus musculus))
- The Rat (Rattus norvegicus)
- For photographs and description on human embryology we refer to the webpages of Dr. Mark Hill of the University of New South Wales, and to the extensive online course (multilingual, including English and Dutch) created by the universities of Fribourg, Lausanne and Bern with the support of the Swiss Virtual Campus.
Importance of knowledge on the descriptive embryology in man and animals
Each multicellular organism starts its life cycle with one single cell, the fertilized oocyte or zygote. The cytology and metabolism of the zygote and of each other cell type is rather comparable. But, the fertilized oocyte has the possibility to divide into daughter cells (blastomeres), which differentiate structurally and functionally in such a way that a multicellular organism is finally formed. This organism finally consists of millions of cells that together arrange complex organ systems. Along with the increase in number of embryonic cells, the organization of the organim changes, organ systems become determined, histological differentiation occurs in the newly formed organs and finally results in the formation of characteristic tissue types. Knowledge on the embryonic development of an animal species is important to obtain insight into the Anatomy of the animals, Phylogeny, Evolution and Systematic classification, as well as into the mechanisms and principles that control the development of
their body plan. Therefore, Descriptive Biology is instrumental for Developmental Biology in which the molecular and regulatory mechanisms underlying developmental processes are unraveled.
Several of these aspects are discussed in the following courses given at the Radboud University Nijmegen: Neurodevelopment
en "Human Embryology and Developmental Biology
, which are taught by Dr. Sharon Kolk.