Estrella Mountain Community College
Estrella Mountain Community College: The Execretory System and Nephrons
This resource provides general information about the human excretory system and kidneys, and a section only about nephrons. It includes several pictures, diagrams and explanations for understanding.
Biology Pages
Kimball's Biology Pages: The Kidneys
An online biology textbook on the structure and function of the kidneys. Full of labeled, color diagrams for better understanding.