Mucus is a thick, slippery substance produced by the mucous membranes in the body. It plays a vital role in protecting and lubricating various organs, such as the nose, throat, and lungs. Mucus helps trap dust, germs, and other particles, preventing them from entering the body and causing infections. In addition to its protective functions, mucus also aids in digestion. The gastrointestinal tract produces mucus to coat and protect the lining of the stomach and intestines. This helps facilitate the movement of food and prevents damage from stomach acids.