Anatomy, Physiology, and Pathophysiology for Allied Health, first edition, is an introductory book to the body systems for medical assisting students. It acquaints students with basic information about all of the body systems. The book speaks directly to the student, with chapter introductions, case studies, and chapter summaries written to engage the student’s attention. When referring to patients in the third person, we have alternated between passages that describe a male patient and passages that describe a female patient. Thus, the patient will be referred to as “he” half the time and as “she” half the time. The same convention is used to refer to the physician. The medical assistant is consistently.