Final answer:
The axillary artery is renamed the brachial artery as it enters the arm and continues to supply blood to the brachial region and its surroundings.
Step-by-step explanation:
The axillary artery changes its name to the brachial artery once it enters the arm. Specifically, as the axillary artery continues from the axillary region into the upper arm, known as the brachium, it is then referred to as the brachial artery.
This artery is responsible for supplying blood to much of the brachial region and gives off several branches, including the deep brachial arteries and the ulnar collateral arteries, that provide blood to the posterior surface of the arm and the elbow region, respectively.
Eventually, the brachial artery bifurcates into the radial and ulnar arteries at the coronoid fossa.