The sinuses produce mucus that helps to moisturize the interior of the nose, according to Cedars-Sinai. Mucus traps dust, dirt, pollutants and microorganisms at the entry to the respiratory system and prevents their travel into the lungs. The sinuses also reduce the weight of the skull and affect voice tone.
WebMD describes the sinuses as a group of interconnected hollow cavities in the skull surrounding the nose. Pink tissue lines the sinuses, which are empty with the exception of a thin layer of mucus covering the tissue. This mucus material drains into the nose through a series of ducts that attach each sinus cavity to the nose. Sometimes, allergens cause the nose and sinuses to overreact resulting in an overproduction of mucus. Infections in the sinuses also cause them to produce more mucus and results in a stuffy head, sinus pressure and pain.
The open-air cavities that form the sinuses help to reduce the weight of the bone that forms the skull, according to the Ohio Sinus Institute. These cavities also provide protection during trauma, serving as a crumple zone to prevent the impact from damaging the brain.
The National Center for Biotechnology Information indicates the maxillary sinus serves as a resonance chamber for the voice. This open space changes the tone of the voice. The sinuses are much more complex in shape than a straight organ pipe, giving the human voice more depth and character.