This document provides an overview of anatomy and physiology (A&P) and key concepts. It describes that A&P is the study of the structure and function of the body and its parts. The body is organized in a hierarchy from atoms to organ systems. There are 11 organ systems that work together to carry out 7 basic needs for life: maintaining homeostasis, movement, responsiveness, digestion, metabolism, excretion, and reproduction. Key anatomical terms are also defined, such as anatomical position, directional terms, body planes (sagittal, frontal, transverse), body cavities (dorsal, ventral), and open body cavities.