Educational puzzles for understanding gastrointestinal physiology

C M Bailey1, C T Hsu, S E DiCarlo

  • 1Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan 48201, USA.

Related Concept Videos

What is Monogastric Digestion?01:50

What is Monogastric Digestion?

The human body contains a monogastric digestive system. In a monogastric digestive system, the stomach only contains one chamber in which it digests food. Several other animal species also have monogastric digestive systems, including pigs, horses, dogs, and birds. This chapter, however, focuses on the human digestive system.
Anatomy of the Intestines01:23

Anatomy of the Intestines

Although digestion of proteins, carbohydrates, and lipids may begin in the stomach, it is completed in the intestine. The absorption of nutrients, water, and electrolytes from food and drink also occurs in the intestine. The intestines can be divided into two structurally distinct organs—the small and large intestines.
Small Intestines
The small intestine is an ~7 meter-long tube with an inner diameter of just 2.5 cm. Since most nutrients are absorbed here, the inner lining of the small...
Histology of the Small Intestine01:27

Histology of the Small Intestine

The small intestine exhibits a unique histological structure that significantly enhances its function in digestion and nutrient absorption. These structures include circular folds, villi, and various specialized cells that collectively facilitate the digestion of food.
The intestinal lining features transverse folds called circular folds, each housing fingerlike projections known as intestinal villi. These villi are covered by a layer of simple columnar epithelium, also referred to as...
Physiology of the Gastrointestinal System II: Digestion and Absorption01:22

Physiology of the Gastrointestinal System II: Digestion and Absorption

The gastrointestinal (GI) tract, extending from the mouth to the anus, plays a pivotal role in the digestion and absorption of nutrients. This process involves both mechanical and chemical actions facilitated by various enzymes.
Digestion begins in the mouth, where food undergoes mechanical breakdown by chewing and combines with saliva. Salivary amylase, an enzyme in saliva, starts the breakdown of starches into maltose. The food then travels down the esophagus to the stomach.
In the stomach, a...
Physiology of the Gastrointestinal System III: Elimination01:26

Physiology of the Gastrointestinal System III: Elimination

The gastrointestinal elimination process involves a complex interplay of neural and hormonal mechanisms that coordinate the final waste removal from the body. This intricate operation encompasses the absorption of water and electrolytes, vital for transforming the remaining indigestible food matter into feces. The large intestine is pivotal in water and electrolyte absorption, forming feces from unabsorbed minerals, undigested food, bacteria, bile pigments, and shed epithelial cells. Essential...
Imaging Studies III: Gastrointestinal Motility Studies and Virtual Colonoscopy01:26

Imaging Studies III: Gastrointestinal Motility Studies and Virtual Colonoscopy

This lesson explores three gastrointestinal imaging techniques: radionuclide testing, colonic transit studies, and virtual colonoscopy.
Radionuclide Testing
Radionuclide testing is a sophisticated medical technique for assessing gastrointestinal motility. It focuses on gastric emptying and colonic transit time. Radioactive markers track the movement of food through the digestive system, providing insights into gastrointestinal disorders.
In gastric emptying studies, a meal's liquid and solid...