Biology 3338A Lecture Notes - Lecture 13: Activin And Inhibin, Neural Tube, Gastrulation

• School: Western University
• Department: Biology
• Course: Biology 3338A
• Professor: Sashko Damjanovski

Document Summary

Only focus on frog dorsal organizer in this lecture. Dorsal organizer important for vertebrates because job is to make dorsal axis which includes making head ! Frog embryos cortical rotation where cytoplasm swirls to end up with grey crescent. Rmr experiment where tied frog embryo with one version splitting grey crescent equally but other version giving one embryo half all the grey crescent only half with grey crescent formed axis. This occurs because grey crescent responsible for forming dorsal organizer ! Right picture shows that part of embryo opposite to sep is posterior ie. whatever happens in this location makes dorsal organizer ! Move dorsal organizer into another part of embryo autonomous specification so still makes dorsal mesoderm (dorsal organizer) ie. forms another dorsal axis. Top right shows that in terms of gastrulation, mesoderm ring flips itself inside out at dorsal. Thus dorsal mesoderm is so important because it basically patterns out everything around it !