Artery

In the syllabus and the exam

Artery questions are almost always comparative, pairing an artery against a vein so candidates can explain structural differences in terms of the pressure each vessel must withstand. Candidates must state that an artery has a thick wall with a substantial layer of muscle and elastic fibre to withstand and smooth out the high pressure surge produced each time the heart contracts, a narrow lumen, and no valves because backflow is not a risk under such high forward pressure. A frequent diagram-based question shows cross-sections of an artery, a vein and a capillary side by side and asks candidates to identify each one and justify the identification using wall thickness, lumen size and the presence or absence of valves, rather than by lumen shape alone. The exception candidates must remember is the pulmonary artery, which is unusual in carrying deoxygenated blood from the heart to the lungs, so it is not safe to state that an artery always carries oxygenated blood without this qualification.

Example

The aorta is the widest artery in the body and carries oxygenated blood away from the left ventricle at high pressure.

Related terms

VeinCapillaryDouble circulation

Source:SRC-DSKP-EN