Where does mucus pass?

Mucus passes through various parts of the body, primarily in the respiratory and digestive systems. In the respiratory tract, it traps dust, pathogens, and other particles, helping to keep the airways clear. In the digestive system, mucus lubricates the intestinal walls and protects the lining of the stomach. Mucus is also secreted in other areas, such as the reproductive and urinary tracts, serving protective and lubricating functions.