Gall Bladder -- stores and concentrates bile for release into the duodenum (Fig. 16-20).

Clinical note: A common disorder of the gallbladder is cholelithiasis or the formation of gallstones. These are concretions of cholesterol monohydrate, calcium salts, and phospholipid which can cause painful inflammation of the gallbladder and/or obstruction of the cystic duct and distention of the gallbladder. Treatment often involves surgical removal of the gallbladder.

Examine sections of gall bladder (slide 94 and 105).

• Identify the major layers and the differences within the layers found along the GI tract.
• Note the prominent mucosal folds (Fig. 16-21).
• Also note the type of epithelium lining the lumen and its very thin basement membrane.

What type of epithelium lines the gall bladder and what is its function?

How do the folds and the nature of the epithelial lining facilitate the function of the gall bladder?

How might “gall stones” begin to form?

Now for the endocrine system.