The epithelial lining of the gallbladder is a distinctive simple columnar epithelium. Which specialized structural feature of these cells facilitates bile concentration?
- A Tall columnar cells with numerous microvilli on the apical surface (brush border) facilitating water absorption ✓
- B Numerous goblet cells interspersed among columnar cells that secrete mucus
- C Stratified squamous epithelium resistant to bile salts
- D Transitional epithelium that expands during bile filling
Explanation
The gallbladder mucosa is lined by simple columnar epithelium with prominent apical microvilli (brush border). These cells actively transport sodium (and passively, water follows) from the bile lumen into the lamina propria and submucosal capillaries, concentrating bile 5-10 fold by removing water and inorganic salts. The mucosa also has deep mucosal folds (rugae when contracted, flattened when distended) and oblique mucosal glands (Rokitansky-Aschoff sinuses are herniations of epithelium through the muscular layer — important in cholecystitis). There are no goblet cells in normal gallbladder epithelium.
Reference: BD Chaurasia's Human Anatomy, 8th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.