The brain needs a good blood supply to work properly and stay healthy. It mainly gets this blood from two pairs of big arteries: the carotid arteries and the vertebral arteries.

1. Carotid Arteries:

   • The internal carotid arteries are important blood vessels. They go up the neck and enter the skull through a special opening called the carotid canal.
   • These arteries split into two main branches:
     • Middle Cerebral Artery (MCA): This branch supplies blood to the side surfaces of the brain. It’s important for movement and feeling.
     • Anterior Cerebral Artery (ACA): This branch provides blood to the front part of the brain and the upper middle parts, which are important for thinking and decision-making.

2. Vertebral Arteries:

   • The vertebral arteries travel along the spine and also enter the skull through a big opening called the foramen magnum.
   • These arteries join together to form the Basilar Artery, which sends blood to the brainstem (the part that controls many basic functions) and the cerebellum (the part that helps with balance). Some important branches of this artery include:
     • Posterior Cerebral Arteries (PCA): These arteries supply blood to the back part of the brain and the lower part of the temporal lobes, which are important for seeing.

3. Circle of Willis:

   • This is a special connection at the base of the brain. It links the carotid and vertebral arteries.
   • The Circle of Willis is very important because it helps keep blood flowing to the brain, even if one of the arteries gets blocked.

All these blood vessels are very important for delivering oxygen-rich blood to different parts of the brain. Knowing how they work is essential for understanding brain health and medical studies related to the brain.