Sitemap

health advisory Hospital Doctor Yu 2007-11-8 19:08:50

Basic Embryology.

Answers:

Ditto on druid's answer. All three germ layers develop from the same "layer" (in a simple explanation, after gastrulation, the ecotoderm gives rise to the rest of the germ layers) . therefore, they can't REALLY be separated out, even after full development. Hence, the notochord is actually a derivative of all 3. This is quite interesting and has many implications for much deeper research into embryology and the "sense" system after birth and onward . things like synesthesia, perception, "consciousness," etc., and on.

The following link is a simple (doesn't get in depth into the explanation), yet GREAT diagram. Enjoy!

http://www.luc.edu/depts/biology/dev/lay.

---

Actually, it is the mesoderm which develops between the ectoderm and the endoderm. The notochord then develops from the mesoderm.

---