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.
Tigers are the largest of the four big cats. They have a body length between 1.4 and 2.8 m (4.5 - 9.25 ft), a shoulder height between 80 and 110 cms (31 - 43 inches), a tail length between 60 and 110 cms (24 - 43 inches) and they weigh between 100 and 300 kgs (220 - 660 lbs).