Final answer:
A 'pyloro spasm' is a sudden involuntary contraction of the pylorus, which regulates the passage of chyme from the stomach to the duodenum via the pyloric sphincter. The movement of food through the digestive system is generally facilitated by peristalsis, a similar involuntary wave-like contraction of smooth muscles.
Step-by-step explanation:
The phrase 'Pyloro __' is likely meant to be completed with the word 'spasm,' which describes the sudden involuntary contraction of the pylorus. The pylorus is an important feature in the digestive system that serves as a muscular valve or sphincter controlling the passage of chyme from the stomach to the small intestine. During the digestive process, gastric emptying occurs when rhythmic mixing waves force small amounts of chyme through the mostly closed pyloric sphincter into the duodenum. The pylorus ensures that only liquids and small food particles can pass, regulating the release so the small intestine isn't overwhelmed. Sphincters throughout the digestive system, such as the gastro-esophageal sphincter, similarly act as valves to control the flow of digestive contents.
Peristalsis is a related concept, referring to rapid, involuntary, wave-like contractions of smooth muscles that push food through the gastrointestinal tract. However, peristalsis typically describes the broader movement through the digestive system, not the specific action of the pylorus.