CK-12 Foundation
Ck 12: Biology: Urinary System
[Free Registration/Login may be required to access all resource tools.] Discusses how the urinary system filters blood and excretes wastes.
Inner Body
Innerbody: Digestive System
Take a look inside the human body's digestive system. This site features diagrams of the digestive tract and each part is accompanied by labels and descriptions. Just select an organ by moving the mouse over its image.
CK-12 Foundation
Ck 12: Biology: Excretory System Study Guide
This comprehensive study guide covers the main terms and concepts needed for a unit on the excretory system.
CK-12 Foundation
Ck 12: Life Science: 11.36 Excretory System
Understand the structure and function of the human Excretory system.
National Cancer Institute at the National Institutes of Health
Seer Training Modules: Introduction to the Urinary System
Self-guided learning activity where students learn about the structure and function of the human urinary system. There is a short quiz at the end of the lesson to check for understanding.
McGraw Hill
Glencoe Biology: Excretory System: Self Check Quiz
This multiple-choice quiz on the excretory system allows students to get hints for each question and check their answers after submitting.