Which sequence correctly lists the four layers of the gallbladder wall from outermost to innermost?

Which sequence correctly lists the four layers of the gallbladder wall from outermost to innermost?

• A. Outer serosal layer; Subserosal; Muscular layer; Inner epithelial layer
• B. Inner epithelial layer; Muscular layer; Subserosal; Outer serosal
• C. Muscular layer; Outer serosal layer; Inner epithelial layer; Subserosal
• D. Inner epithelial layer; Subserosal; Outer serosal; Muscular layer

Answer: (A)

The layers of the gallbladder wall run from the outside in as serosa, subserosa, muscular layer, and then mucosa (the inner epithelial layer). The serosa is the outermost covering, followed by a thin subserosal connective tissue layer, then the smooth muscle of the muscular layer, and finally the mucosa lining the interior, with its epithelial cells. This order matches the described sequence: outer serosal layer, subserosal, muscular layer, and inner epithelial layer. Other sequences would misplace the mucosa relative to the subserosa or serosa, which doesn't reflect the actual anatomy of the gallbladder wall.

The layers of the gallbladder wall run from the outside in as serosa, subserosa, muscular layer, and then mucosa (the inner epithelial layer). The serosa is the outermost covering, followed by a thin subserosal connective tissue layer, then the smooth muscle of the muscular layer, and finally the mucosa lining the interior, with its epithelial cells. This order matches the described sequence: outer serosal layer, subserosal, muscular layer, and inner epithelial layer. Other sequences would misplace the mucosa relative to the subserosa or serosa, which doesn't reflect the actual anatomy of the gallbladder wall.