Epithelial cells in the respiratory tract protect the aveoli from infection by secreting mucus that traps bacteria and other particles. Micro villi push the mucus back up towards the digestive system in something called a "mucus escalator".
In chronic smokers these epithelial cells actually change type, removing the mucus escalator function. This loss of function is the pathophysiology behind smokers cough, as they must cough up the mucus they produce.
pseudostratified columnar epithelium
Ciliated epithelium is located in the lining of most body cavities. Some of the cavities that have ciliated epithelium are the lungs, trachea, and nose. Ciliated epithelium serves to keep dust and debris out of the lungs and control the flow of mucus.
Pseudostratified columnar epithelium can be found in the respiratory tract, specifically in the lining of the trachea and bronchi.
Psuedostratified epithelial tissue is epithelial tissue that looks as though it is multiple layers, i.e. stratified, but actually each cell is anchored to the basement membrane. It can be found chiefly lining the respiratory tract.
Pseudostratified columnar epithelium is typically found lining the respiratory tract, where it helps to trap and move mucus and particles out of the lungs. It appears layered, but all cells are attached to the basement membrane, giving it a false appearance of stratification.
Trachea's inner lining(lining that faces the hollow side) is comprised of ciliated epithelium which rests on a basement membrane made of protein fibers. In between the ciliates cells the goblet cells are situated. Beneath the epithelium is an area of loos tissue and tracheal glands that secrets mucus (both tracheal glands and goblet cells secrets mucus so don't get confused which one produces mucus). There is a C-Shaped cartilage in outer lining that supports the trachea.
Pseudostratified columnar epithelium (ciliated form)
False. The epithelium at the trachea level is typically pseudostratified ciliated columnar epithelium, which helps to filter and moisten the air as it passes through the respiratory tract.
Covering epithelium covers body surfaces and components of organs, providing protection, absorption, or secretion. Lining epithelium lines cavities and tubes, serving similar functions as covering epithelium but in a different location. Glandular epithelium forms glands that secrete substances such as hormones or enzymes into the blood or cavities.
Simple epithelium is found lining surfaces where exchange of materials occur, such as the lining of blood vessels (endothelium), the alveoli of the lungs (alveolar epithelium), and the small intestine (simple columnar epithelium). It is also present in areas involved in absorption and secretion, like kidney tubules and the lining of the small intestine.
These are usually simple squamous epithelial cells. The epithelium lining the body cavities is called the mesothelium and is where the cancer mesothelioma arises from. The epithelium lining arteries and veins is called endothelium.
Epithelium is a layer of animal tissue. It can be found in the lining of certain organs and glands in the body.