If you are planning a hard-to-get Alcatraz tour, you will need to really layer clothes for a variety of temperatures. The weather varies greatly from month to month and hour to hour. Even the neighborhood youre in makes a difference. For many visitors, the San Francisco weather can be counter-intuitive.
The carotid arteries are major blood vessels in the neck that supply blood to the brain, neck, and face. There are two carotid arteries, one on the right and one on the left. In the neck, each carotid artery branches into two divisions: 1  The internal carotid artery supplies blood to the brain.
Carotid (ka-ROT-id) artery disease is a disease in which a waxy substance called plaque (plak) builds up inside the carotid arteries. You have two common carotid arteries, one on each side of your neck. They each divide into internal and external carotid arteries.The internal carotid arteries supply oxygen-rich blood to your brain. The external carotid arteries supply oxygen-rich blood to your face, scalp, and neck.ou have two common carotid arteries, one on each side of your neck. They each divide into internal and external carotid arteries. The internal carotid arteries supply oxygen-rich blood to your brain. The external carotid arteries supply oxygen-rich blood to your face, scalp, and neck.