The prediction is: if the simple squamous epithelium in lungs is replaced by stratified epithelium, The respiratory membrane will not be permeable to the exchange of oxygen and carbon dioxide.
The simple squamous epithelium covers the surfaces ensuring the passive transport (diffusion) of either gas (as in the lungs) or liquids (as in the walls of the blood capillaries).
Simple squamous epithelia also form the delicate lining of the pleural, pericardial and peritoneal cavities where it allows the passage of tissue fluid into and out of these cavities. Although these cells appear to be simple in shape, they have important and varied roles.
The stratified epithelium is not involved in significant uptake, in permeability of molecules, or in secretory activity, but merely provides a more robust coating than would be offered by a single epithelium.
