What is the typical atmospheric pressure at sea level?

• A. 760 mm Hg
• B. 600 mm Hg
• C. 850 mm Hg
• D. 1013 mm Hg

Answer: (A)

The typical atmospheric pressure at sea level is traditionally defined as 760 mm Hg, which corresponds to the height of a mercury column that can be supported by the pressure exerted by the atmosphere at that elevation. This value is a standard reference point in meteorology and is used universally in various calculations involving gases, including those related to respiratory physiology and ventilation.

In practical terms, 760 mm Hg is equivalent to approximately 1013.25 hPa (hectopascals), which is often rounded to 1013 hPa for convenience in weather reporting and other scientific contexts.

Understanding this standard pressure is crucial for calculations related to gas exchange in the pulmonary system, as it affects the partial pressures of gases, thereby influencing diffusion and other gas exchange processes.