What role does the diaphragm play in the human body?

The diaphragm plays a crucial role in the human body by separating the thoracic cavity, which houses the heart and lungs, from the abdominal cavity, which contains organs such as the stomach, liver, and intestines. This muscular structure forms a barrier between the two cavities, allowing for distinct environments for the organs situated within each space.

In addition to its anatomical separative function, the diaphragm is also important for respiration. When the diaphragm contracts during inhalation, it creates a vacuum effect that draws air into the lungs. This illustrates its essential dual role in both structure and function within the respiratory system.

The other options do not accurately describe the diaphragm's primary function. Regulating blood flow pertains more to the circulatory system, controlling vision relates to the eyes and neural pathways, and managing body temperature is regulated by the integumentary and endocrine systems.