Diagram from cancer.gov:
Rugae can be seen within stomach.
The purpose of the gastric rugae is to allow for expansion of the stomach after the consumption of foods and liquids.
Rugae can appear in the following locations in humans:
- Wrinkles of the scrotum
- Hard palate immediately behind the upper anterior teeth
- Inside the urinary bladder
- Inside the stomach
Difference between rugae and intestinal villi
Rugae are only evident when an organ or tissue is deflated or relaxed. For example, rugae are evident within the stomach when it is deflated. However, when the stomach distends, the rugae unfold to allow for the increase in volume. On the other hand, plicae remain folded regardless of distension as is evident within the plicae of the small intestine walls.
- Moore, Keith L & Dalley, Arthur F (2006). Clinically Orientated Anatomy (5 ed.). Philadelphia: Lippincott Williams & Wilkins. p. 250.