Epithelial Tissues – Covering and Lining

Vocabulary flashcards reviewing major epithelial tissue types, their structures, locations, and functions, along with key related cellular features.

Simple cuboidal epithelium

Single layer of cube-shaped cells with centrally placed nuclei; lines ovary surface, lens capsule, pigmented retina, kidney tubules, and small gland ducts; functions in secretion and absorption.

Nonciliated simple columnar epithelium

Single layer of column-shaped cells with nuclei near base plus goblet cells and microvilli; lines GI tract, many gland ducts, and gallbladder; specialized for secretion and absorption.

Ciliated simple columnar epithelium

Single layer of ciliated column-shaped cells, sometimes with goblet cells; lines bronchioles, uterine tubes, uterus, paranasal sinuses, spinal cord canal, and brain ventricles; ciliary action moves mucus or oocytes.

Pseudostratified ciliated columnar epithelium

Appears multilayered but all cells contact basement membrane; ciliated variety lines most upper respiratory tract; secretes mucus and moves it via cilia.

Pseudostratified nonciliated columnar epithelium

Similar structure without cilia or goblet cells; lines larger ducts of glands, epididymis, and part of male urethra; functions in absorption and protection.

Stratified squamous epithelium

Many layers with flattened apical cells; keratinized type forms skin surface, nonkeratinized lines moist cavities such as mouth, esophagus, and vagina; provides protection against abrasion, water loss, and microbes.

Stratified cuboidal epithelium

Two or more layers with cube-shaped apical cells; found in ducts of sweat and esophageal glands and part of male urethra; offers protection plus limited secretion and absorption.

Stratified columnar epithelium

Several layers of irregular cells with columnar apical layer; lines part of urethra, large excretory ducts, anal mucous membrane, and conjunctiva; provides protection and secretion.

Transitional epithelium

Variable cell shapes; apical cells cuboidal when relaxed and squamous when stretched; lines urinary bladder, ureters, and parts of urethra; permits organ distension.

Goblet cell

Unicellular gland embedded in columnar epithelium that secretes mucus to lubricate and protect the lining of organs such as the intestine and trachea.

Microvilli

Microscopic fingerlike projections on the apical surface of absorptive epithelial cells that greatly increase surface area for absorption.

Cilia

Motile, hair-like extensions of the plasma membrane that beat in coordinated waves to move mucus and other substances across an epithelial surface.

Basement membrane

Thin extracellular layer anchoring epithelium to underlying connective tissue; provides structural support and regulates molecule exchange.