View source for Simple columnar epithelium

{{short description|Tissue type}}
{{refimprove|date=April 2021}}
{{Infobox anatomy
| Name        = simple columnar epithelium
| Latin       = epithelium simplex columnare
| Image       = Normal gastric mucosa intermed mag.jpg
| Caption     = The [[stomach]] [[gastrointestinal wall|wall]], with simple columnar epithelium visible as a lining at the top.
}}
{{Epithelia series}}
'''Simple columnar epithelium''' is a single layer of columnar [[Epithelium#Cell types|epithelial cell]]s which are tall and slender with oval-shaped [[Cell nucleus|nuclei]] located in the basal region, attached to the [[basement membrane]]. In humans, simple columnar epithelium lines most organs of the [[digestive tract]] including the [[stomach]], and [[intestines]]. Simple columnar epithelium also lines the [[uterus]].

==Structure==
{{See also|Cilia|Mucociliary clearance}}
Simple columnar epithelium is further divided into two categories: ciliated and non-ciliated (glandular). The ciliated part of the simple columnar epithelium has tiny hairs which help move mucus and other substances up the respiratory tract.

The shape of the simple columnar epithelium cells are tall and narrow giving a column like appearance. the apical surfaces of the tissue face the lumen of organs while the basal side faces the [[basement membrane]].<ref name=":0">{{Cite web|title=Simple epithelium|url=https://www.kenhub.com/en/library/anatomy/simple-epithelium|access-date=2021-03-19|website=Kenhub|language=en}}</ref> The nuclei are located closer along the basal side of the cell.<ref name=":0" />

Absorptive columnar epithelium is characterized as having a striated border on its apical side, this border is made up of [[non-motile]] microvilli allowing for increase surface area for absorption.<ref name=":0" /> These are known as non-ciliated columnar epithelium. Non-ciliated simple columnar epithelium is made up of glandular [[goblet cell]]s which secrete [[mucin]] to form [[mucus]].<ref name=":0" /> The rest of the cell is made up of cytoplasm with membrane bound [[secretory granule]]s which secrete the mucin, and are found towards the apical surface of the cell.<ref name=":0" />

===Ciliated===
{{See also|Respiratory epithelium}}
'''Ciliated columnar epithelium''' has many [[cilia]] which moves [[mucus]] and other substances via [[mucociliary clearance]] in the [[respiratory tract]].

It is present in the lining of the [[fallopian tubes]], where currents generated by the [[cilia]] propel the [[egg cell]] toward the [[uterus]].

Ciliated columnar epithelium forms the [[neuroepithelium]] of the [[ependyma]] that lines the [[Ventricular system|ventricles of the brain]] and [[central canal]] of the [[spinal cord]]. These cilia move the [[Cerebrospinal fluid|cerebro-spinal fluid]] (CSF).

===Non-ciliated===
These are found in the lining sections of the [[gastrointestinal tract]] (inner lining of [[oesophagus]], [[stomach]], etc.) and may be [[brush border]]ed.
<gallery>
File:Gray1059.png|Vertical section of a villus from the dog's small intestine. X 80. (Simple columnar epithelium labelled at right, third from the top.)
File:Gray1060.png|Transverse section of a [[Intestinal villus|villus]], from the human [[intestine]]. X 350.<br>a. [[Basement membrane]], here somewhat shrunken away from the epithelium.<br>b. [[Lacteal]].<br>c. [[Columnar epithelium]].<br>d. Its striated border.<br>e. [[Goblet cells]].<br>f. [[Leucocytes]] in epithelium.<br>f’. Leucocytes below epithelium.<br>g. [[Blood vessels]].<br>h. [[Muscle cells]] cut across.
</gallery>

== Function ==
* Secretion<ref name=":0" />
* Absorption<ref name=":0" />
* Protection<ref name=":0" />

== References ==
<references />

==External links==
* {{KansasHistology|epithel|epith05}}
* {{UIUCHistologySubject|1061}}

{{Epithelial types}}
{{Authority control}}

[[Category:Epithelial cells]]