In the developing heart of a human embryo, the cavity of the primitive atrium becomes subdivided into right and left chambers by a septum, the septum primum, which grows downward into the cavity. The increasingly smaller gap below it (before it fuses with the endocardial cushion) is known as the ostium primum (i.e. "the first opening"). The septum primum eventually fuses with the endocardial cushion, closing the ostium primum off completely. Meanwhile, perforations appear in the superior part of the septum primum, forming the ostium secundum (i.e. "the second opening"). This will eventually form part of the fossa ovalis.
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This article incorporates text from a public domain edition of Gray's Anatomy.
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| | Heart development |
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| Vasculogenesis,
angiogenesis,
and lymphangiogenesis | | Development of arteries | |
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| | Development of veins | |
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| | Development of lymph vessels | |
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| Development of circulatory system
about teeth near children |
- anuli: Anulus sanguineus perienameleus
- lacunae: Lacuna sanguinea supraenamelea
- Ductus sanguineus mesialis
- Ductus sanguineus distalis
- Ductus sanguineus lingualis
- Ductus sanguineus palatinus
- Ductus sanguineus buccalis
- Ductus sanguineus labialis
- Lacuna sanguinea apicalis
- Lacuna sanguinea periodontalis
- Lacuna sanguinea parodontalis
- Lacuna sanguinea gingivalis
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| Extraembryonic
hemangiogenesis | |
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| | Fetal circulation | |
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noco/cong/tumr, sysi/epon, injr
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proc, drug (C1A/1B/1C/1D), blte
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anat (a:h/u/t/a/l,v:h/u/t/a/l)/phys/devp/cell/prot
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noco/syva/cong/lyvd/tumr, sysi/epon, injr
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proc, drug (C2s+n/3/4/5/7/8/9)
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