Protein signalling in heart development Protein signalling in heart development The heart is the first functional organ in a vertebrate embryo. There are 5 stages to heart development. Specification of cardiac precursor cells: The lateral plate mesoderm delaminates to form two layers: the dorsal somatic (parietal) mesoderm and the ventral splanchnic (visceral) mesoderm. The heart precursor cells come from the two regions of the splanchnic mesoderm called the cardiogenic mesoderm. These cells can differentiate into endocardium which lines the heart chamber and valves and the myocardium which forms the musculature of the ventricles and the atria. The heart cells are specified in anterior mesoderm by
How Many Words How Many Words "How Many Words" is the official second single by the singer-songwriter Blake Lewis, from his debut album "A.D.D. (Audio Day Dream)". The song was expected to be followed by "Know My Name", and then "Without You". However, due to being dropped by Arista Records, "How Many Words" is the final single from his debut album. He is expected to release a single from his second album at the end of 2009. The single was released to mainstream radio format on March 10, 2008. Also, an EP featuring remixes of the song was released onto iTunes on May