The pear-shaped gallbladder shows marked variation in size and shape among different individuals. Anatomically, it consists of a neck, a body, and a blindly ending fundus. Histologically, its wall consists of a mucosa, a muscularis, a perimuscular layer of connective tissue, and a serosa or fibrosa.

Mucosa - The mucosa consists of an epithelium, its basement membrane, and an underlying lamina propria of loose connective tissue. The tall, simple columnar epithelial cells of the mucosa are absorptive in nature. They have basal ovoid nuclei and on their luminal surface is a thin striated border (demonstrated by EM). No goblet cells are present in this epithelium. The mucosa of the non-distended gallbladder is irregularly folded, somewhat resembling villi when it is sectioned. These folds largely disappear when the gallbladder is filled.

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=== Slide 152 Liver and Gallbladder, (H&E) ===