The heart has upper and lower chambers.
Atrial means pertaining to the upper chamber of the heart.
Frogs have 3 heart chambers
atrial
The combining form for the upper chamber of the heart is "atri/o".
The atria are found in the heart, specifically in the upper chambers. There are two atria in the heart, the left atrium and the right atrium, which receive blood from the veins and pump it into the ventricles.
The upper chamber on the right side of the heart.
The left atrium
The left atrium
The right atrium (upper chamber) and the right ventricle (lower chamber)
The lower chamber is the ventricle, and there are 2 upper chambers (they are known as atria).
its location is in the upper heart chamber that is smaller than a ventricle.