Final answer:
Particles trapped in nasal mucus are removed from the body through the action of cilia that line the respiratory tract, which move the mucus towards the throat, where it can be expelled or swallowed and destroyed by stomach acids.
Step-by-step explanation:
How Particles in Mucus are Eliminated:
The respiratory system has built-in mechanisms to remove particles trapped in mucus (nasal). As we breathe, air passes through the nasal cavity, where particles are trapped by mucus and hairs. The nasal passages and the rest of the respiratory tract, including the bronchi and bronchioles, are lined with cilia, which are hair-like projections. These cilia move in a coordinated wave-like motion known as the mucociliary escalator, pushing the mucus with the trapped particulates away from the lungs and towards the throat. Once in the throat the mucus containing foreign particles can be expelled by sneezing, coughing, or clearing the throat, or it can be swallowed.
If swallowed the mucus goes down the esophagus into the stomach where acidic digestive juices destroy the trapped particulates and pathogens. Coughing especially serves as a reflex to forcefully remove mucus and debris from the upper respiratory tract. Cilia and mucus also play a role in the gastrointestinal, urinary and reproductive tracts, where they trap pathogens and help to expel them from the body. All these processes ensure that foreign particles and pathogens are constantly being moved out of the body to maintain respiratory health.