Ignore this box please.
More
Settings
Goodies
About
Help
Feedback
PRIVACY
DontTrack
DontBubble
Policy
COMMUNITY
Platform
Forum
Chat
Spread
Search syntax
s:d sort by date
r:uk uk region
site: domain search
\ search first result
More...
r:n turn off region
!a search search amazon
site:uk uk pages
f: find files
t: within title
b: within body
More explanation...
Ostium primum
In the developing heart, the atria initially communicate with each other by an opening between the free edge of the septum primum and the AV cushions, known as the ostium primum, below the free margin of the septum.
More at Wikipedia
Embryology
This page requires Javascript.Get the non-JS version
here
.