The digestive system intakes food, digests and absorbs nutrients, and excretes waste which is important for energy and anabolism of proteins. The three body tissues in the histology art are Duodenum, Esophagus, and Liver Lobule.

The duodenum has been characterized as a segment in the small intestine in the form of a C or a horseshoe. This section of the small intestine is named for its size, “12 fingers” in Latin, referring to the organ’s approximate length. Its role is to receive pancreatic enzymes. Additionally, the duodenum links to the liver through a structure known as the hepatoduodenal ligament. This juncture is where the duodenum receives bile for mixing with chyme, a critical part of the chemical digestion process.

The esophagus is a hollow, muscular tube that connects the neck and stomach. The esophagus goes through the center of the chest cavity, known as the mediastinum, and has two sphincters to control opening and closing. Periodic contractions (peristalsis) perform the passing of food from the mouth to the stomach is performed by periodic contractions (peristalsis). During vomiting, these contractions are reversed, allowing stomach contents to be thrown out.

Liver lobules are hexagonal and composed of hepatocyte plates separated by sinusoids. Sinusoids are tiny blood vessels that carry oxygen and nutrients into the liver cells via their capillary walls. The lobules are linked to small bile ducts, which eventually unite to create the hepatic duct. The liver lobules are known as the liver’s functional units.