Describe the flow of an RBC from the right atrium through to the aorta. How might this change if there was a hole between the two atria? When/why might you want a hole between the two atria?

SVC, RA, RAVV/Tricuspid, PA, PV, LA, LAVV/Bicuspid, LV, Aorta, Body.Because the RV has a higher pressure than the LA, a hole between the atria would largely result in blood flow bypassing the ventricle in favour of the lower pressure LA. This would mean blood would not pass through the lungs and would therefore also not get oxygenated. You do not want blood to pass through the lungs as a foetus, as the foetus does not breath and the lungs are not inflated. In fact, the lungs are fluid-filled, creating a high resistance environment against blood flow.