Kidneys are a filter system. The main job of the kidneys is to remove waste from the blood and return the cleaned blood back to the body. Each minute about one litre of blood ï­ one-fifth of all the blood pumped by the heart - enters the kidneys through the renal arteries.
The volume of helium in the balloon has been estimated as being able to lift a total load, including the balloon material and the structure beneath it, of 65 pounds (29 kg) at sea level and 48 pounds (22 kg) at 8,000 feet (2,400 m).
When you blow up a balloon, you force extra air into it, creating higher air pressure inside the balloon than outside of it. Given the chance, the air molecules will move to a lower-pressure environmentâwhich is why, if you let go of a balloon's opening without tying it off, air you added will rush out again.