What is the study of the functions of the human body known as?

The study of the functions of the human body is known as physiology. This branch of biology focuses on understanding how various systems and organs operate, how they interact, and how they maintain homeostasis within the body. Physiology encompasses various functions, such as the mechanisms of breathing, circulation, digestion, and muscle movement, providing insight into how the body responds to different stimuli and maintains balance.

In contrast, anatomy is the study of the structure of the body and its organs, often examining their physical relationships. Biochemistry investigates the chemical processes and substances that occur within living organisms, while embryology studies the development of embryos from fertilization to birth. Each of these fields is significant in its own right, but physiology specifically addresses how different systems in the body function, making it the correct choice for this question.