Final answer:
The deep palmar arch is an extension of the radial artery, which, in collaboration with the ulnar artery, forms the vascular supply to the hand and fingers.
Step-by-step explanation:
The deep palmar arch is primarily the distal extension of the radial artery. The radial artery, formed at the bifurcation of the brachial artery, parallels the radius and gives off smaller branches until it reaches the carpal region. At this point, it fuses with the ulnar artery to form both the superficial and deep palmar arches. The deep palmar arch, along with the superficial palmar arch formed from this anastomosis, supply blood to the hand and digital arteries.