Where are the receptors that trigger the sneeze reflex located?

• A. Trachea
• B. Pulmonary artery
• C. Nasopharynx
• D. Bronchioles

Answer: (C)

The receptors that trigger the sneeze reflex are located in the nasopharynx. This reflex is primarily designed to expel irritants from the nasal cavity and upper respiratory tract. When these irritants—such as dust, pollen, or other allergens—stimulate the sensory receptors in the nasopharynx, signals are sent to the brain, which then orchestrates the explosive action of a sneeze to clear the irritants.

The involvement of the nasopharynx in this reflex underscores its role as a protective mechanism for the respiratory system, helping to maintain clear airways and prevent the entry of potentially harmful substances. Understanding the anatomical location of these receptors is crucial for recognizing how the body responds to foreign particles and helps protect the respiratory system from potential damage.