Depending on recipe and cooking method it may be either a flaky potato pie, or a heavy potato pudding.
Ductus arteriosus: A short vessel through which blood headed from the heart via the pulmonary artery to the lungs is shunted before birth. This blood is shunted away from the lungs and returned to the aorta. When the shunt is open, it is said to be patent.
Patent mean open. The ductus arteriosus is a blood vessel connecting the main vessel leading to the lungs (pulmonary artery) to the main vessel of the body (aorta). Before birth, the mother and placenta take care of the oxygen needs of the fetus (baby before birth). The fetus does not need to use his/her lungs.