Place the following in order from highest to lowest expected partial pressure oxygen levels.

• cells of systemic tissues
• atmospheric air
• systemic capillaries
• pulmonary capillaries
• alveoli of lungs

Atmospheric air

Alveoli of lungs

Pulmonary capillaries

Systemic capillaries

Cells of systemic tissues

Explanation:

Partial pressure of oxygen levels in the blood is very important for the oxygen diffusion.Partial pressure  of oxygen is defined as the amount of pressure exerted by oxygen in the blood. If two adjacent areas have a different partial pressure of the oxygen, the oxygen will move from the area of higher concentration to the area of lower concentration until it reaches equilibrium. So this is a principle by which oxygen is picked up from the atmospheric air, transported through the capillaries and other vessels and delivered to the cells of systemic tissues.

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