This website was developed by undergraduate biology researchers working with Dr. Karen Bernd at Davidson College.

Simple Cuboidal Epithelium

Classification & Structure

The term ‘cuboidal’ might seem confusing if you were to look at the apical surface of cuboidal epithelial cells and only see hexagonal shapes.   Despite this external appearance, a cut that is perpendicular to the surface of the cells would show that the cells are equally wide as they are tall, creating a square profile with a spherical nucleus at its center (Figure 1). Simple cuboidal cells are classified as simple since they consist of only a single layer of cells. Depending on their location, some simple cuboidal cells, such as the ones lining the surface of the lines the lumina of convoluted tubules in the kidney, may have microvilli on their surface (not shown in figure). To learn more about the general classification and structure of epithelial cells, see the Structure of Epithelial Tissue on our home page.

Figure 1. Diagram of simple cuboidal epithelium.


By lining the surface of various ducts of various glands and organs, simple cuboidal cells are able to provide a layer of protection from abrasion, foreign particles, invading bacteria and excessive water loss (due to its selective permeability) to the underlying tissue. In the kidney tubules, the cells aid in the absorption and transport of filtered substances. In the kidney tubules, the cells aid in the absorption and transportation of filtered substances.  To learn more about these functions and other general functions of epithelial cells, check out the Functions section on our home page.


Simple cuboidal epithelium lines the surface of small excretory ducts in various organs and glands in the body, compose some of the kidney tubules in the kortex of the kidney, and create the covering of the ovary. Several examples of their locations are discussed below.

Kidney Tubules

In the kidney, simple cuboidal epithelium lines the lumina of convoluted tubules. The polarity of the cells enables the basal lateral surface (which is in contact with the basal lamina and the underlying tissues) and the apical surface (which lines the lumen where the particles are) to have different surface proteins. These distinct surfaces allow the simple cuboidal cells to facilitate in the absorption and transportation of substances that are filtered by the kidney (Figure 2). In the proximal convoluted tubules, the apical surface of the epithelium is lined with microvilli, creating a brush border, giving it a fuzzy appearance. The microvilli can aid in helping to transport material by “brushing” the molecules in the lumen of the tubules.

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Figure 2. A slide of the the kidney medulla showing simple cuboidal epithelium lining the lumina (indicated by the lu) of some convoluted tubules. The areas are pointing at the edge of the tubule, where the darker line of pink is the basement membrane.

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Figure 3. Germinal epithelium made up of simple cuboidal cells that covers the ovary.

Covering of the Ovaries

On the ovarian surface, simple cuboidal cells make up the ovarian surface epithelium and are modified peritoneum that is derived from the mesothelium that covered the developing ovaries (Figure 3). Simple cuboidal epithelial cells’ ability to rapidly divide and proliferate enables them to repair ovulatory defects that occur on the ovarian surface, especially during the time of ovulation. There have also been studies linking the majority of ovarian cancer causes to the simple cuboidal layer.

Respiratory Bronchiole

Simple cuboidal epithelium lines the wall of the respiratory bronchiole (Figure 4) and may have cilia in the proximal portion of the bronchiole.  The single layer of simple cuboidal epithelium enables the respiratory bronchioles to create a transitional zone where air conduction and exchange of gases or respiration can take place.
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Figure 4.Simple cubodial epithelium lines the wall of the smaller respiratory bronchiole.

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Hart, K. (2007). "Epithelial tissue: Simple Cuboidal Epithelium". Histology Photomicrographs. Peninsula College. 5 Sept 2010 <>

Gartner, L.P. & Hiatt, J.L. (2007). Color Textbook of Histology (3rd ed.). Philadelphia, PA: Saunders Elsevier.

Wiechmann, A. & Pillow J. "Female Reproductive System". Interactive Histology Atlas. University of Oklahoma Health Science Center. 10 Sept. 2010. <>

Wiechmann, A. & Pillow J. "Respiratory System". Interactive Histology Atlas. University of Oklahoma Health Science Center. 10 Sept. 2010. <>

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