Ontario Grade 11 University Biology Practice Text

The main function of mucous membranes in the respiratory system is to moisten and filter the air that we breathe. These membranes are lined with mucus-producing cells that secrete mucus, which serves several important roles. Firstly, the mucus traps dust, pathogens, and other airborne particles, helping to purify the air before it reaches the lungs. This is crucial for preventing infections and maintaining respiratory health. Secondly, by adding moisture to the air, the mucous membranes help to prevent the respiratory tissues from drying out, which can lead to irritation and increased vulnerability to infection. This function of mucous membranes is vital, as it supports efficient gas exchange in the lungs by ensuring that the air is not only clean but also optimally conditioned. Without adequate moisture and filtration, the respiratory system could be more prone to SAMPLEinflammation and infection, negatively impacting overall health.