Editing Gallbladder and biliary tree (section)

== '''Microscopic anatomy''' ==

* '''Gallbladder'''
** Wall composed of      fibromuscular tissue with non-striated muscle cells arranged in circular,      oblique and longitudinal fashion
** Layers
*** Mucosa - single layer       cuboidal epithelium
*** Lamina propria (no       submucosa or muscularis mucosae)
*** Muscularis externa - thin       but strong fibromuscular layer
*** Serosa - derives from       peritoneum, completely invests the fundus but covers the body and neck       only on the opposite side to liver
* '''Bile duct'''
** Walls are composed of      fibro-areolar tissue and contain no muscle within their walls apart from      the occasional myocytic cell
** Lined by columnar epithelium      which contains mucus-secreting glands