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.
Very old, large male alligators reach an expected maximum size of up to 4.6 m (15 ft) in length, weighing up to 453 kg (999 lb), while females reach a maximum of 3 m (9.8 ft). On rare occasions, a large, old male may grow to an even greater length.