The human body is a complex machine full of organs and pieces connected in such a way as to allow us to breathe, grow, feed ourselves, interact with each other and reproduce. But how is it organised? What are the systems that allow the human body to work? In this unit, we will discover how everything works: what our vital functions and organs are, which systems are responsible for each function, how certain systems are interconnected, and why we're made the way we are. Body systems that are featured include the circulatory system, respiratory system, digestive system, skeletal system, and muscular system.