Anatomy & Physiology

Lesson Title: Human Digestive System
Academic Standards: HS-LS1-2, HS-LS1-3
Content Creator: Wendy Martin
Level: High School
Duration: 30-40 min
  /  Human Digestive System


  • Describe the overall functions of the digestive system
  • Differentiate between the organs of the alimentary canal
  • Observe the anatomy of digestive organs
  • Assemble the digestive tract


This lesson allows students to work hands-on with organs involved in the human digestive system. Not only will students examine each organ individually to understand its purpose and function, but also, students will assemble the digestive tract in order to better understand the entire digestive process.


  1. Review class objectives
  2. Hypothesize patient digestive issues
    1. Students gather around patient on gurney and offer ideas
  3. Show video clip of human digestive system
  4. Discuss each digestive system organ
    1. Teacher distributes organs to student pairs, one at a time
    2. Discusses structure and function of each organ
  5. Assemble digestive organs within human cadaver
    1. Students are paired; organs are set next to cadaver in random order
  6. Take field trip to synthetic cadaver lab
  7. Debrief lesson and assign homework

Suggested Ancillary Support


  • Alimentary Canal: organs that food moves through
  • Accessory Organs: liver, gallbladder, pancreas
  • Oral Cavity (teeth & tongue)
  • Saliva softens food
    • Mechanically grind up food
    • Adults have 32 teeth?
    • Incisors, canines, premolars, molars
    • Top of tongue covered by papillae
    • Taste buds: sweet, sour, salty, bitter, umami
    • Involved in chewing, swallowing, tasting, speaking
  • Esophagus
    • Sphincter valve prevents backflow
    • Connects pharynx to stomach
    • Moves food through peristalsis
  • Stomach
    • Gastric juices begin chemical digestion
    • Mucus protects it from its own acidity
    • Mechanically churns food
  • Small Intestine
    • Longest portion; averages 6-7 meters in length
    • Duodenum, jejunum, ileum
    • Completes chemical digestion
    • All nutrient absorption occurs here
  • Large Intestine
    • Feces compaction
    • Water and electrolyte reabsorption
    • Referred to as the colon
    • Ascending, transverse, descending, sigmoid colons
    • Averages 1.5 meters in length