Days 21 Latin cor tubulare | Precursor splanchnic mesoderm Code TE E5.11.1.1.1.0.5 | |
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The tubular heart or primitive heart tube is the earliest stage of heart development.
From the inflow to the outflow, it consists of sinus venosus, primitive atrium, the primitive ventricle, the bulbus cordis, and truncus arteriosus.
It forms primarily from splanchnic mesoderm. More specifically, they form from endocardial tubes, starting at day 21.
References
Tubular heart Wikipedia(Text) CC BY-SA