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.
A gigantic great white shark measuring more than 20 feet long has been spotted by cage divers near Mexico. The massive predator, nicknamed Deep Blue, was spotted in the waters near Mexico's Guadalupe Island. The shark, who is estimated to be around 50 years old, is believed to be one of the largest great white sharks ever seen.