General Anatomy and Processes

Ingestion

The process of taking in food.

Digestion

The mechanical and chemical breakdown of food for the body to use.

Absorption

The process of taking in nutrients for the body.

Compaction

The process of absorbing water and consolidating leftover food into feces.

Mechanical Digestion

The physical breakdown of food into smaller pieces through actions like chewing and stomach contractions.

Chemical Digestion

A series of hydrolysis reactions that break dietary molecules into their base forms.

Hydrolysis Reaction

A chemical process where water is used to cleave the bonds of complex molecules.

Mucosa/Mucous Membrane

The inner lining of the digestive tract made of loose connective tissue and a thin smooth muscle layer.

Submucosa

A thick layer of loose connective tissue containing blood vessels, lymphatics, nerve plexus, and occasionally glands.

Muscularis Externa

The layer of the digestive tract with two layers of muscles responsible for motility in pushing food through the tract.

Serosa

A thin layer of areolar tissue covered by simple squamous epithelium, found in certain parts of the digestive tract.

Adventitia

A fibrous connective tissue layer found in the esophagus and pharynx, blending into neighboring connective tissues.

Gastrin

A hormone produced by the digestive tract that stimulates gastric functions.

Secretin

A hormone produced by the digestive tract that regulates digestive processes.

Paracrine secretions

Substances that diffuse through tissue fluids to stimulate nearby target cells, such as histamine and prostaglandins.