BIOL 3156 Lecture Notes - Lecture 5: Lateral Plate Mesoderm, Primordium, Neural Tube
Document Summary
Heart is the first functional organ in the embryo. Formed by the hypomere mesoderm (lateral plate mesoderm) specifically the splancnic mesoderm. Presumptive primordia exist as a pair of tissues on each side of the embryo. The primordia pushes them together to form the one heart. Primordia migrate in a ventral fashion to fuse and give rise to the simple tube form of the heart. Primordia show up on either side of the neural tube. There is endoderm underneath this that will be split into anterior and posterior endoderm. Pharyngeal area of the endoderm has to be present for the heart to differentiate. Heart forms as paired tubes right and left induction of the cardia bifida. There are two regions on each side of the notochord and neural tube that will differentiate themselves out as the cardiac primordia. These primordia will arise as angiogenic cell clusters. Angiogenic clusters separate from the splanchnic sheet become mesenchymal cells and separate from the heart.
