Which branch of science focuses on the functions of the body and how life-sustaining activities are carried out?

Physiology is the branch of science dedicated to understanding the functions of the body and how various life-sustaining activities are executed. It examines how different systems, organs, cells, and biomolecules interact to maintain homeostasis and perform essential processes that allow organisms to survive and thrive. This includes areas such as how the heart pumps blood, how the lungs facilitate gas exchange, and how muscles contract to enable movement.

Anatomy focuses more on the structure of the body, including organs, tissues, and systems, rather than their functions. Histology involves the microscopic study of tissues and their organization, while biochemistry looks at the chemical processes within and related to living organisms. Each of these fields provides valuable information; however, physiology specifically addresses the underlying mechanisms and dynamics involved in bodily functions, making it the correct choice for this question.