Ok so I would start by saying that light has a maximum speed, then explain that because space is so big we measure it's distance in light years and which means how light travels in a year at 186,282 miles per second Put that in perspective my saying If you could travel at the speed of light, you could go around the Earth 7.5 times in one second. Tell them Sunlight takes about 8 minutes 19 seconds to reach the Earth and that it can take millions or more light years for more distance stars light to reach our telescopes .
Ductus Arteriosus is a blood vessel normally present in fetuses during development. The blood vessel is designed to bypass the pulmonary artery and brings blood to the Descending Aorta, as the fetus cannot breath through the lung (being as they are fluid filled). This is normally not a problem because oxygenated blood comes from the mother's blood supply.
Patent Ductus Arteriosus, is what happens when that vessel does not close. While not as dangerous as other congenital defects. However, because there is still a bypass, blood that normally need to be oxygenated by going through the pulmonary arteries to the lungs, can be diverted and placed into the blood stream without vital oxygen. This condition may eventually lead to CHF (congestive Heart Failure) and Pulmonary Hypertension if not treated.
It carries oxygen to the rest of the body. It can also remove carbon dioxide.
