I think that it protects them because they like swish them about and make them covered by a mucusy layer which then protects them further called bronchilus. this eventully stops any damage at all in the alveoli
At the top of the respiratory system, the nostrils (also called nares) act as the air intake, bringing air into the nose, where it's warmed and humidified. Tiny hairs called cilia protect the nasal passageways and other parts of the respiratory tract, filtering out dust and other particles that enter the nose through the breathed air. :D hope it helps
Alveoli
alveoli
Alveoli
Yes, the colon does secrete mucus to help lubricate the passage of stool and protect its lining from damage.
The lining has to thicken in order to protect the egg that is released.
alveoli sacs <--nova net.
To protect the fetus
The lining tissue in alveoli is primarily composed of simple squamous epithelium. This thin layer of flat cells facilitates efficient gas exchange between the air in the alveoli and the blood in the surrounding capillaries. Additionally, type II alveolar cells, which are cuboidal in shape, produce surfactant to reduce surface tension and prevent alveolar collapse.
The fluid lining the inner alveolar membrane is called surfactant. It helps reduce the surface tension in the alveoli, which prevents them from collapsing in on themselves every time we exhale.
A lining in a pipe, placed there to protect the material of the pipe from the contents that will be passing through the pipe.
Surfactants, which are molecules that lower surface tension, can be found in serous fluid. These molecules help prevent alveoli in the lungs from collapsing by reducing the surface tension of the fluid lining the alveoli.