Final answer:
At sea level under resting conditions, skeletal muscle has a partial pressure of approximately 40 mm Hg for O₂ and 45 mm Hg for CO₂, reflecting the gaseous exchange during internal respiration.
Step-by-step explanation:
Under resting conditions at sea level, the partial pressure of oxygen (O₂) in the skeletal muscle is about 40 mm Hg, and the partial pressure of carbon dioxide (CO₂) is typically around 45 mm Hg. These values reflect the gaseous exchange that occurs during internal respiration. Oxygen is utilized during cellular processes and carbon dioxide is produced as a byproduct, which explains their respective partial pressures in the skeletal muscle. When exercising, the body demands more oxygen and produces more carbon dioxide, which could shift these partial pressures accordingly. However, at rest, these values are maintained to ensure the proper functioning of the body's systems.
The process by which carbon dioxide (CO₂) exits the tissue to enter the blood and the oxygen binds to oxyhemoglobin is part of a delicate balance maintained by the solubility and diffusion gradients of these gases. The increased solubility of CO₂ in comparison to O₂ allows a similar mass of each gas to diffuse despite the different partial pressures.