Internal carotid and vertebral arteries carry blood to the brain. Which of the following describes their role?

Internal carotid and vertebral arteries carry blood to the brain. Which of the following describes their role?

• A. They supply blood to the brain
• B. They drain blood from the brain
• C. They regulate cerebrospinal fluid
• D. They control cranial nerves

Answer: (A)

Their role is to deliver oxygenated blood to brain tissue so neurons can meet their energy needs. The internal carotid arteries bring blood into the brain’s anterior circulation, while the vertebral arteries rise up to form the basilar artery for the posterior circulation; together, they create collateral pathways through the Circle of Willis to maintain perfusion if one route is compromised. They do not drain blood from the brain—that’s the venous system’s job. They also don’t regulate cerebrospinal fluid or control cranial nerves—their primary function is supplying blood to brain tissue.

Their role is to deliver oxygenated blood to brain tissue so neurons can meet their energy needs. The internal carotid arteries bring blood into the brain’s anterior circulation, while the vertebral arteries rise up to form the basilar artery for the posterior circulation; together, they create collateral pathways through the Circle of Willis to maintain perfusion if one route is compromised. They do not drain blood from the brain—that’s the venous system’s job. They also don’t regulate cerebrospinal fluid or control cranial nerves—their primary function is supplying blood to brain tissue.