Anatomy and physiology are closely related concepts that are often studied together. In a few words, anatomy is a study of the physical structure of an organism, while physiology involves the study of the functions of individual structures and systems within an organism, as well as the function of an organism as a whole. An understanding of anatomy is critical to the study of physiology, and learning about physiology is important to people who want to understand how anatomical structures work.
Both anatomy and physiology have been studied for centuries. Humans have always maintained a curiosity about how they and other organisms are put together and how they work. Many people throughout history have also been interested in comparing and contrasting different living organisms to find similarities and identify differences. Cats and fish, for example, have very different bodies that are customized for the environments they live in.
The study of anatomy focuses on learning about the size, shape, and location of structures in the body. It usually centers around dissection, in which examples are carefully cut up to reveal the structures within. Physical structures can be identified with the naked eye, or observed under magnification with a microscope for more detail. During the dissection process, anatomists can carefully document everything they encounter, and see how systems in the body are connected. An imperfect understanding of anatomy can lead to considerable confusion for medical practitioners, as knowing about anatomy is a very important part of studying the progress of disease.
Anatomy could be considered a static study, while physiology is more dynamic, involving the chemical, physical, and electrical processes that make an organism function, from the processes that regulate heart rate to the complex systems involved in visual perception. In order to study physiology, it is often necessary to work with living organisms or tissue to fully understand physical processes, such as the release of neurotransmitters in the brain and the storage of energy in cells. Both anatomy and physiology can be studied with the use of dissection, medical imaging techniques, and laboratory analysis of samples from specimens.
Medical students study these fields extensively over the course of their educations, so that they understand how the body works as a whole, and how the different systems within the body relate to each other. This field is also a topic of interest for people in many allied health professions, ranging from X-ray technicians who need a thorough knowledge of anatomy to do their work to medical dosimetrists who need to understand physiology when calculating appropriate dosages and treatments for cancer.