The document provides an overview of the human body, including: - Leonardo da Vinci was the first to correctly illustrate the human skeleton. Andreas Vesalius wrote an influential book on anatomy and William Harvey discovered blood circulation. - Anatomy studies body structure and morphology while physiology examines body functions. - Key terms are defined for anatomical directions and planes. The body is composed of hierarchical structural units from cells to tissues to organs to systems. Homeostasis maintains the internal stability of the body.