Question

A ring of smooth muscles present between the stomach and the duodenum is
(a) Cardiac Sphincter
(b) Pyloric Sphincter
(c) Ileocaecal Valve
(d) Anal Sphincter

Answer 1

A sphincter is a special round muscle that usually maintains contraction of a natural body passage or opening and which relaxes as essential by regular physiological working. Sphincters are seen in multiple parts of the body and each sphincter varies in function depending on the region it is present.

Complete step by step answer:
A ring of smooth muscle present between the stomach and duodenum is Pyloric Sphincter. The two major parts of the pylorus are the pyloric antrum, which opens to the inside of the stomach, and the pyloric canal which opens to the duodenum of the small intestine. The pyloric sphincter controls the release of digested food from the stomach to the small intestine.

Additional information:
- Major portion of digestion occurs in the small intestine, where all the nutrients are absorbed by the finger- like structures, known as the villi. Villi increases the surface area of the small intestine which aids in more absorption of nutrition to the bloodstream.
Cardiac sphincter: A sphincter located among the food pipe (esophagus) and the stomach, which opens when the food approaches the stomach by rhythmic peristaltic movement.
Ileocecal valve: A unique sphincter muscle that protects the passage of the large intestine. It is found where the ileum of the small intestine joins the colon of the large intestine and maintains the flow between colon and ileum to prevent the bacteria- loaded contents of the colon from infecting the small intestine.
Anal sphincter: A sphincter muscles are present in the anal opening also to control the movement of feces which gets released out of the body.
So, the correct answer is ‘Pyloric Sphincter’.

Note:
- Small intestine is lengthier than the large intestine, but in terms of diameter, the large intestine is bigger than the small intestine.
- The average length of the small intestine is 22 feet which is three times the length of an average human being.
- There is a total of six sphincters present in the body, which are the sphincter of Oddi, pyloric sphincter, anal sphincter, cardiac sphincter, Ileocecal valve, and urinary sphincter.