Digestive System

Exploration of the digestive system from ingestion to defecation.

Digestive systems take many forms. There is a fundamental distinction between internal and external digestion. External digestion is more primitive, and most fungi still rely on it. In this process, enzymes are secreted into the environment surrounding the organism, where they break down an organic material, and some of the products diffuse back to the organism. Later, animals form a tube in which internal digestion occurs, which is more efficient because more of the broken down products can be captured, and the internal chemical environment can be more efficiently controlled.

This video goes over the structure and function of the digestive system. Students will learn about digestion, absorption and elimination. The video will also discuss the differences between mechanical and chemical digestion. Students will also follow food through digestive tract and see the roles of accessory organs in the process of digestion.