Search results
Results from the WOW.Com Content Network
Smooth muscle is grouped into two types: single-unit smooth muscle, also known as visceral smooth muscle, and multiunit smooth muscle. Most smooth muscle is of the single-unit type, and is found in the walls of most internal organs (viscera); and lines blood vessels (except large elastic arteries), the urinary tract , and the digestive tract .
The muscle of the inner layer is arranged in circular rings around the tract, whereas the muscle of the outer layer is arranged longitudinally. The stomach has an extra layer, an inner oblique muscular layer. [1] Between the two muscle layers is the myenteric plexus (Auerbach's plexus). This controls peristalsis.
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.
Mucin is viscous, clear, and clinging. Underlying the mucous membrane in the mouth is a thin layer of smooth muscle tissue and the loose connection to the membrane gives it its great elasticity. [5] It covers the cheeks, inner surfaces of the lips, and floor of the mouth, and the mucin produced is highly protective against tooth decay. [6]
The majority of this type of muscle tissue is found in the digestive and urinary systems where it acts by propelling forward food, chyme, and feces in the former and urine in the latter. Other places smooth muscle can be found are within the uterus, where it helps facilitate birth, and the eye, where the pupillary sphincter controls pupil size. [3]
Stomach contains an additional oblique muscle layer just interior to circular muscle layer. In the upper esophagus , part of the externa is skeletal muscle , rather than smooth muscle. In the vas deferens of the spermatic cord, there are three layers: inner longitudinal, middle circular, and outer longitudinal.
These are known as non-ciliated columnar epithelium. Non-ciliated simple columnar epithelium is made up of glandular goblet cells which secrete mucin to form mucus. [1] The rest of the cell is made up of cytoplasm with membrane bound secretory granules which secrete the mucin, and are found towards the apical surface of the cell. [1]
Gastrointestinal physiology is the branch of human physiology that addresses the physical function of the gastrointestinal (GI) tract.The function of the GI tract is to process ingested food by mechanical and chemical means, extract nutrients and excrete waste products.