Damage to parietal cells may lead to pernicious anemia. The damaged parietal cells fail to produce intrinsic factor which is required for vitamin B₁₂ absorption. Deficiency of vitamin B₁₂ causes pernicious anaemia.

In paralytic phase of ischemia, decrease in bowel motility results in abdominal bloating.

Absorption of vitamin B₁₂ takes place in the terminal ileum.

Patients are prohibited from taking caffeine in irritable bowel syndrome (IBS) because caffeine is a very powerful GI tract irritant. It can aggravate IBS.

Absorption of water and inorganic mineral nutrients in ruminants occurs in the omasum part of the digestive tract. Omasum is the third compartment of the stomach of ruminants. The omasum wall is highly folded, giving a large surface area which allows for the efficient absorption of water and salts released from the partially digested food.

Parietal cells are only found in the fundic region and are acidophilic. They secrete gastric acid and intrinsic factor.

Brunner's glands are located in the submucosa of duodenum. Their  function is to protect duodenum from acidic chyme by secreting alkaline mucus rich in bicarbonate. They also secrete urogastrone, which inhibits chief cells and parietal cells from secreting HCL and other acidic enzymes.

The cephalic phase occurs at the sight, thought and smell of food, which stimulates the cerebral cortex. Cephalic phase causes ECL (enterochromaffin-like cells) to secrete histamine and increases HCl acid in the stomach.

Eating faeces of mother is a characteristic that is found in panda. They eat faeces to obtain the bacteria that are required to properly digest vegetation found in their ecosystems. When they are born, their intestines do not contain these bacteria as they are sterile.

Enteroendocrine cells of the stomach secrete various hormones, including alpha and gamma endorphin. Endorphin plays a role in reducing pain.

A damaged vagus nerve cannot send signals to the stomach muscles. This may cause food to remain in the stomach longer, rather than move normally into the small intestine to be digested. This condition is called gastroparesis or paralysis of stomach.

Rokitansky-Aschoff sinuses are present in the gall bladder. These are pockets in the wall of gall bladder or the outpouchings of gall bladder mucosa into the gall bladder muscle layer.

Acetylcholine is released in the gastric phase of digestion to stimulate gastric juices. It acts on the gastrin to stimulate the release of gastric juice.

Transcobalamin-1, also known as haptocorrin, is present in saliva. It strongly binds and protects B₁₂ molecules from stomach acids as they enter the stomach. After B₁₂-haptocorrin complexes pass from the stomach via the pylorus to the duodenum, pancreatic proteases cleave haptocorrin from B₁₂ molecules. 

EGF is produced by sub-mandibular gland and plays an important biological effect on salivary EGF, including the healing of oral and gastroesophageal ulcers and in the inhibition of gastric acid secretion.