The heart, like the circulatory and lymphatic systems, is a derivative of the mesoderm. The heart takes its origin from the union of the two rudiments, which, merging, are closed into a heart tube, in which the tissues characteristic of the heart are already represented. The endocardium is formed from the mesenchyme, and the myocardium and the epicardium are formed from the splacnotoma visceral leaflet.
Primitive heart tube in this heart 3D model is divided into several parts:
render: Vray Adv 3.00.07
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