ANATOMY

Detailed explanation-1: -Peristalsis is a series of wave-like muscle contractions that move food through the digestive tract. It starts in the esophagus where strong wave-like motions of the smooth muscle move balls of swallowed food to the stomach.

Detailed explanation-2: -Waves of muscle contractions called peristalsis (pronounced: per-uh-STALL-sus) force food down through the esophagus to the stomach. A person normally isn’t aware of the movements of the esophagus, stomach, and intestine that take place as food passes through the digestive tract.

Detailed explanation-3: -The esophagus contracts as it moves food into the stomach. A “valve” called the lower esophageal sphincter (LES) is located just before the opening to the stomach. This valve opens to let food pass into the stomach from the esophagus and it prevents food from moving back up into the esophagus from the stomach.

Detailed explanation-4: -Acetylcholine causes the muscle layer of the digestive organs to squeeze with more force and increase the “push” of food and juice through the digestive tract. It also causes the stomach and pancreas to produce more digestive juice.

Detailed explanation-5: -The esophagus is a muscular conduit connecting the pharynx and the stomach. Its function is controlled by an intrinsic nervous system and by input from the central nervous system through the vagus nerve.