Principles of Human Physiology - Gastrointestinal System

These flashcards cover key terms and concepts related to the gastrointestinal system, particularly focusing on the secretion and regulation of digestive substances.

Saliva

A digestive fluid secreted by salivary glands containing enzymes that initiate the digestion of carbohydrates.

Stomach Acid

A solution of hydrochloric acid (HCl) produced by the parietal cells of the stomach, essential for digestion and killing pathogens.

Pancreatic Juice

A bicarbonate-rich fluid secreted by the pancreas that contains digestive enzymes necessary for digesting proteins, carbohydrates, and fats.

Bile

A digestive fluid produced by the liver and stored in the gallbladder that aids in the emulsification and absorption of fats.

Gastrin

A hormone produced by G cells in the stomach that stimulates acid and pepsinogen secretion.

Pepsinogen

An inactive enzyme secreted by chief cells in the stomach that is activated to pepsin by stomach acid.

Secretin

A hormone that is released in response to acidity in the duodenum, leading to the secretion of bicarbonate-rich fluid from the pancreas.

CCK (Cholecystokinin)

A hormone that stimulates the release of bile from the gallbladder and pancreatic enzymes in response to fats and proteins in the duodenum.

Cephalic-phase control

The initial phase of gastric secretion triggered by the sight, smell, or taste of food.

Gastric-phase regulation

The phase of gastric secretion triggered by the presence of food in the stomach, involving chemoreceptors and mechanoreceptors.