What is Mesocardium?
Medical Definition of mesocardium 1 : the transitory mesentery of the embryonic heart. 2 : either of two tubular prolongations of the epicardium that enclose the aorta and pulmonary trunk and the venae cavae and pulmonary veins.
What is the dorsal mesocardium?
The dorsal mesocardium (dorsal mesentery of the heart), formed by splanchnic mesoderm located beneath the foregut, maintains the positioning of the primitive heart tube within the pericardial cavity.
What happens to the dorsal Mesocardium?
The single heart tube is suspended from the foregut into the primitive thoracic cavity by dorsal mesocardium which eventually ruptures to allow looping of the primitive heart tube.
What are the three layers of the heart?
Three layers of tissue form the heart wall. The outer layer of the heart wall is the epicardium, the middle layer is the myocardium, and the inner layer is the endocardium.
What are Truncoconal ridges?
The two truncoconal ridges (neural crest cells and cells originating from the second heart field) grow toward each other and fuse first at the truncoconal transition before closing distally (toward the outflow tract) and proximally (toward the ventricles).
What is cardiogenic field?
The cardiogenic field is initially horseshoe-shaped and surrounded by cardiac myoblasts with the cardiogenic field’s apex, eventually developing into primitive ventricles along with their respective outflow tracts. By doing so, it forms a primitive heart tube continuous with vascular structures.
What does the bulbus cordis become?
The bulbus cordis develops into the right ventricle, whereas the primitive ventricle becomes the left ventricle. The interventricular septum separating these begins to form about day 28. The atrioventricular valves form between weeks five to eight. At this point, the heart ventricles resemble the adult structure.
What is the cardiogenic region?
The heart begins to develop near the head of the embryo in a region known as the cardiogenic area. Following chemical signals called factors from the underlying endoderm (another of the three primary germ layers), the cardiogenic area begins to form two strands called the cardiogenic cords ([link]).
What is the function of pericardium?
The pericardium acts as mechanical protection for the heart and big vessels, and a lubrication to reduce friction between the heart and the surrounding structures. A very important role in all aspects of pericardial functions is played by mesothelial cells.