The largest artery in your body is the Aorta. The largest vein in the body is Vena Cava. The aorta is the largest blood vessel in the body. It is an artery that directly arises from the heart itself and descends through the thorax and into the abdomen. All the arteries of the body, save the pulmonary arteries, stem from the aorta or one of its main branches.
There are many different dinosaur books that state different sizes of the tyrannosaurus rex. These sizes range from 40 feet long to 49 feet long. It's maximum length was probably close to 50 feet long. The paleantologists have only found remains, incomplete remains, of the Tyrannosaurus.
Supersaurus is among the largest dinosaurs known from good remains, possibly reaching 33 to 34 meters (108 to 112 ft) in length, and a weight of 35 to 40 tons. The first described specimens of Supersaurus were individual bones that suggested a large diplodocid. A large cervical vertebra from the same quarry was later assigned to Supersaurus which indicated an incredibly long neck. This vertebra measures 1380mm and is the longest cervical known.