Opening in the septum primum between the two atria of the embryonic heart[TMD]. [ http://medical-dictionary.thefreedictionary.com/foramen+primum http://en.wikipedia.org/wiki/Primary_interatrial_foramen ]

Synonyms: primary interatrial foramen ostium primum interatrial foramen primum

This is just here as a test because I lose it

Term information

database cross reference
external definition

First of the two openings to perforate the septum primum between the two atria of the embryonic heart. [TFD][VHOG]

homology notes

The tetrapod clade develops a complete atrial septum and loses the fifth aortic arch altogether. [ISBN:978-0030223693 Liem KF, Bemis WE, Walker WF, Grande L, Functional Anatomy of the Vertebrates: An Evolutionary Perspective (2001) p.620]; [about heart development] In the various tetrapod classes ontogenetic events essentially recapitulate the phylogenetic stages.[well established][VHOG]

id

UBERON:0009149