columnar

Examples of columnar in the following topics:

• Types of Epithelial Tissue

  • The four major classes of simple epithelium are: 1) simple squamous; 2) simple cuboidal; 3) simple columnar; and 4) pseudostratified.
  • Simple columnar epithelium is a single row of tall, closely packed cells, aligned in a row.
  • These are simple columnar epithelial cells whose nuclei appear at different heights, giving the misleading (hence pseudo) impression that the epithelium is stratified when the cells are viewed in cross section.
  • Stratified epithelia can be columnar, cuboidal, or squamous type.
  • Columnar epithelium has cells taller than they are wide.

• Testes Ducts

  • The epithelium of the tubule consists of Sertoli cells, which are tall, columnar type cells that line the tubule.
  • The ductuli are unilaminar and composed of columnar ciliated and nonciliated (absorptive) cells.

• Epithelial Membranes

  • Most mucous membranes contain stratified squamous or simple columnar epithelial tissue.

• Absorption in the Small Intestine

  • The inner wall, or mucosa, of the small intestine is lined with simple columnar epithelial tissue.

• Mucosa

  • In the stomach the epithelium is simple columnar, and is organized into gastric pits and glands to deal with secretion.

• Skin and Mucosae (Surface Barriers)

  • In the stomach it is simple columnar, and is organised into gastric pits and glands to secrete acids and pepsin.
  • The small intestine epithelium is specialised for absorption; it is organised into simple columnar epithelium on protruding villi with narrow crypts, that have a high surface area.

• Anatomy of the Large Intestine

  • The wall of the large intestine is lined with simple columnar epithelium.

• Nose and Paranasal Sinuses

  • The paranasal sinuses are a group of four paired air-filled spaces, lined with respiratory epithelium (ciliated columnar epithelium), that are named according to the bones within which the sinuses lie: surrounding the nasal cavity (maxillary sinuses), above the eyes (frontal sinuses), between the eyes (ethmoid sinuses), and behind the ethmoid bone (sphenoid sinuses).

• Tonsils

  • For example, the adenoids and tubal tonsils are covered with the ciliated psuedostratified columnar epithelium of the nasopharynx, while the palatine and lingual tonsils are made up of the non-keratinized stratified squamous epithelium of the oropharynx.

• Trachea

  • It is lined with pseudostratified ciliated columnar epithelium cells with goblet cells that produce mucus.