Why pseudostratefied cilliated columnar epithelial cells vs just plain cilliated columnar

[ebrown1985]

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Hi all. Some might take this as a philosophical question, but why does the respiratory system mostly consist of pseudostratefied cilliated columnar vs. just plain cilliated columnar epithelial cells? Is there a known physiological reason that makes pseudostratefied cells more of a fit for this region?

 

[Med Ed]

What are the three main cell types present in the respiratory epithelium?

 

[piii]

What are the three main cell types present in the respiratory epithelium?

Pseudostratified, goblet, lymphocytes?

 

[ebrown1985]

What are the three main cell types present in the respiratory epithelium?

When speaking of the epithelial types, it starts with pseudostratefied columnar through the trachea into the bronchioles (most if not all of the conducting zone) which will become simple squamous as you progress closer to the alveoli (in the respiratory zone). I think my question is more pertaining to why specifically pseudostratefied columnar vs. just columnar. I'd imagine cilliated columnar could support goblet cells and lymphocytes with no problem. Is there an added advantage that pseudostratification offers that simple columnar doesn't?

 

[Med Ed]

Pseudostratified, goblet, lymphocytes?

Lymphocytes are not resident cells.

Better answer: columnar, basal, and goblet.

Now, which one puts the pseudo- in pseudostratified?

 

[ebrown1985]

Lymphocytes are not resident cells.

Better answer: columnar, basal, and goblet.

Now, which one puts the pseudo- in pseudostratified?

The columnar cells are the ones that are pseudostratefied, but they all touch the basal cell layer which is what makes is pseudo. Correct?

 

[Med Ed]

The columnar cells are the ones that are pseudostratefied, but they all touch the basal cell layer which is what makes is pseudo. Correct?

If there were not basal cells the layer would simply be ciliated columnar cells with interspersed goblet cells. The question of true versus pseudostratification would never have been posited. Hence, the basal cells are the culprit. They are the ones that make the epithelium look somewhat stratified.

The basal cells are, of course, a distinct cell population that performs functions not encompassed by the others. So if the question is "why does the lung have pseudostratified respiratory epithelium?" the answer is that the lung apparently needs basal cells.