Baroreceptors are stretch-sensitive mechanoreceptors located in blood vessels that detect changes in blood pressure and help regulate cardiovascular function. They are primarily located in which arterial regions?

• A. Venous sinuses
• B. Capillary beds
• C. Aortic arch and carotid sinus
• D. Lymph nodes

Answer: (C)

Baroreceptors are stretch-sensitive sensors that monitor arterial pressure and feed rapid feedback to keep blood pressure within a normal range. They are located mainly in the walls of the aortic arch and at the carotid sinus (where the carotid artery branches). When BP rises, the walls stretch more, increasing the firing rate of these receptors; the brainstem then activates responses that slow the heart and relax or widen vessels to lower pressure. When BP falls, reduced stretch lowers firing, and the body responds by increasing heart rate and vascular tone to raise pressure. This quick reflex helps maintain stable blood pressure in the short term. Other sites like venous sinuses, capillary beds, or lymph nodes aren’t the primary arterial sensors for this reflex.