If the mucus in the air track of mammals dry up and the hairs in the nostrils are removed

If the mucus in the air track of mammals dry up and the hairs in the nostrils are removed, impure air would be breathed into their lungs. The mucus and hairs in the nostrils serve as filters that trap dust, dirt and other harmful particles that could enter the respiratory system. Without these protective mechanisms, impure air would pass through the nostrils and enter the lungs, potentially causing harm to the respiratory system. The drying up of mucus would also make it difficult for the cilia in the airways to move mucus up and out of the respiratory system, which could lead to the accumulation of mucus and further respiratory problems.