PSEUDOSTRATIFIED EPITHELIUM – 2
The pseudostratified epithelium shown in this page lines the inner cavity of the trachea. It is also called respiratory epithelium although it does not participate in the exchange of gases between the blood and the inhaled air.
Observe the nuclei at various heights of the epithelial layer, but they are not organized in distinct layers, as would be the case of a stratified cubic-prismatic epithelium already seen previously on page 2-16.
Place the cursor or click on the figure to see epithelial cell nuclei – some nuclei of columnar cells are highlighted in light blue and those of some basal cells in dark blue. Below the basal cells you find connective tissue.
Between the epithelial cells you can see mucus secreting epithelial cells called goblet cells because their shape remind glass goblets. Their cytoplasm is poorly stained, because mucus does not stains well with hematoxylin and eosin and the nucleus is placed at the cell base.
Lymphocytes are often present in this epithelium.
The nucleus of a goblet cell is highlighted in dark green after moving the mouse. Its cytoplasm, where the secretion is concentrated, appears in light green.
Another important feature of the epithelium lining the trachea is the presence of cilia on the free surface of its columnar cells. They are the pink band after moving the mouse or clicking
Observe the nuclei at various heights of the epithelial layer, but they are not organized in distinct layers, as would be the case of a stratified cubic-prismatic epithelium already seen previously on page 2-16.
Place the cursor or click on the figure to see epithelial cell nuclei – some nuclei of columnar cells are highlighted in light blue and those of some basal cells in dark blue. Below the basal cells you find connective tissue.
Between the epithelial cells you can see mucus secreting epithelial cells called goblet cells because their shape remind glass goblets. Their cytoplasm is poorly stained, because mucus does not stains well with hematoxylin and eosin and the nucleus is placed at the cell base.
Lymphocytes are often present in this epithelium.
The nucleus of a goblet cell is highlighted in dark green after moving the mouse. Its cytoplasm, where the secretion is concentrated, appears in light green.
Another important feature of the epithelium lining the trachea is the presence of cilia on the free surface of its columnar cells. They are the pink band after moving the mouse or clicking
