Carotid artery disease is caused by a buildup of plaques in arteries that deliver blood to your brain. Plaques are clumps of cholesterol, calcium, fibrous tissue and other cellular debris that gather at microscopic injury sites within the artery. This process is called atherosclerosis.
Great white sharks may not be the world's biggest sharks, since that title goes to the whale shark, but they are the planet's largest known predatory fish. Whale sharks and great whites couldn't be more different in temperament.
Spotty11222/Wikimedia Commons/Public Domain. Not only was Megalodon the biggest prehistoric shark that ever lived; it was the largest marine predator in the history of the planet, vastly outweighing both the modern Great White Shark and ancient reptiles like Liopleurodon and Kronosaurus.