Exam 37: Gas Exchange & Transport

If anything decreases alveolar PO₂, how does that affect the alveolar-blood oxygen pressure gradient?

The presence of hemoglobin in the blood approximately doubles the oxygen-carrying capacity of plasma alone.

Hemoglobin is made up of four polypeptide chains: an alpha, a beta, a gamma, and a delta.

An increase in the partial pressure of carbon dioxide decreases the affinity between hemoglobin and oxygen. This is called a right shift, or the Haldane effect.

One factor that determines the amount of oxygen transferred from the lungs to the blood is the total functional surface area of the respiratory membrane.

To produce the highest possible oxygen concentration in the blood, gas exchange occurs in only one direction at the respiratory membrane-from the lung to the blood.

There are six iron atoms in a single hemoglobin molecule.

One reason that carbon monoxide gas is so dangerous is that it attaches to hemoglobin more readily than does oxygen gas.

Blood is distributed through the capillaries in a layer so thin that each red blood cell comes in contact with the alveolar-capillary membrane.

An increase in the plasma PCO₂ and a decrease in PO₂ cause an increase in the dissociation of CO₂ from hemoglobin.