You'll continue learning about the organ systems in this lesson. To start out, you'll learn about how human organ systems are interrelated and how a problem with one system will affect the others. You'll then move on to a discussion of the integumentary (skin), digestive, urinary, respiratory, and reproductive systems. Just like in Lesson 5, you'll learn about each system's organs, function, and some common disorders. You'll finish the lesson with a discussion of the most important concept in human physiology—homeostasis. Homeostasis means the drive of your body to keep many different variables, like blood pressure and temperature, within a certain range. You'll find out why this is so crucial and how you might be asked to monitor homeostasis while caring for patients.