Search results
Results from the WOW.Com Content Network
The pylorus of the stomach has a thickened portion of the inner circular layer: the pyloric sphincter. Alone among the GI tract, the stomach has a third layer of muscular layer. This is the inner oblique layer and helps churn the chyme in the stomach.
Diagram of the alkaline mucous layer in the stomach with mucosal defense mechanisms. The gastric mucosa is the mucous membrane layer of the stomach, which contains the gastric pits, to which the gastric glands empty. In humans, it is about one mm thick, and its surface is smooth, soft, and velvety.
The inner part of the stomach wall is the gastric mucosa a mucous membrane that forms the lining of the stomach. the membrane consists of an outer layer of columnar epithelium, a lamina propria, and a thin layer of smooth muscle called the muscularis mucosa. Beneath the mucosa lies the submucosa, consisting of fibrous connective tissue. [17]
It is the innermost layer of the stomach. [5] It is affected by the hormone histamine, which signals it to release hydrochloric acid (HCl). Sub-mucosal layer – This layer consists of different vessels and nerves, ganglion neurons, and adipose tissue. It is the second layer of the stomach and supports the mucosa. [6]
Pepsin is a protease that can digest and damage stomach cells. To prevent these disastrous effects, mucus and bicarbonate ions (HCO 3 −) are secreted by the foveolar cells. The mucus allows the acid at pH above 4 to penetrate lining, but below pH 4 (i.e. when acid is more concentrated) the acid cannot penetrate the mucus.
The inner circular is helical with a steep pitch and the outer longitudinal is helical with a much shallower pitch. [23] Whilst the muscularis externa is similar throughout the entire gastrointestinal tract, an exception is the stomach which has an additional inner oblique muscular layer to aid with grinding and mixing of food.
It is present in the lining of the fallopian tubes, where currents generated by the cilia propel the egg cell toward the uterus. Ciliated columnar epithelium forms the neuroepithelium of the ependyma that lines the ventricles of the brain and central canal of the spinal cord. These cilia move the cerebro-spinal fluid (CSF).
The gastric mucosal barrier is the property of the stomach that allows it to safely contain the gastric acid required for digestion. If the barrier is broken, as by acetylsalicylic acid (ASA, aspirin) in acid solution, acid diffuses back into the mucosa where it can cause damage to the stomach itself.