A sphincter.
The Sphinctea
There is no bodily organ that does this.
sphincter
The stomach!
It regulates the exit of partially digested food from the stomach and is in the lower region of the stomach
The cardiac sphincter is located at the top of the stomach and controls the direction of food passing through the esophagus so that no food will re enter the esophagus. The Pyloric sphincter stops bile and digested food from entering the stomach, this valve is located at the bottom of the stomach.
The pylorus produces digestive enzymes. The pancreas of a frog release enzymes into the small intestine to help break down food. The pylorus is the lower area in the stomach joining to the duodenum.
esophagus helps digest food
The pyloric sphincter valve.
The contractions of the stomach propels the food into the small intestine
Acid (Hcl) is secreted by the parietal cells of the stomach. In the stomach the food itself and saliva from mouth (this is little alkaline) regulates acidity of the stomach. But acid in normal quantity is needed for digestion, specially for meats, hard and solid foods.
After being broken up in the stomach, the chyme (partially digested food after exiting the stomach) is absorbed into tiny hairs in the small and large intestines called villi. Hope this helps :)