Final answer:
The left internal carotid artery supplies blood to the left side of the head and neck.
Step-by-step explanation:
The left internal carotid artery supplies blood to the left side of the head and neck. This artery arises directly from the aortic arch, while the right internal carotid artery arises from the brachiocephalic artery. The left internal carotid artery continues through the carotid canal of the temporal bone and gives rise to branches that supply blood to the frontal, temporal, and parietal lobes of the cerebrum.