Which anatomical structures are primarily involved in the cough reflex?

The cough reflex is a protective mechanism that helps clear the airways of irritants, mucus, and foreign objects. The primary anatomical structures involved in this reflex include the lungs, airways, diaphragm, and specific nerve pathways.

When an irritant is detected in the airways, sensory receptors located in the throat, trachea, and bronchi are activated. These receptors send signals through sensory nerves to the cough center in the brain, which then orchestrates the cough response. This involves the diaphragm and the muscles of the chest to expel air forcefully from the lungs. As air is expelled, it carries along with it any irritants, thereby protecting the respiratory system.

The other options include structures that either do not directly participate in the cough reflex or serve different functions within the body. For example, the heart and blood vessels are involved in cardiovascular processes but not directly in coughing. Similarly, the stomach and liver play roles in digestion, while nasal passages and sinuses might be involved in other reflexes related to respiratory defense but not specifically in the cough reflex mechanism itself.