Question

How is it that red blood cells can bind oxygen in the lungs but then offload it near body cells that need it?

a)A conformational change caused by high pH causes the oxygen to detach near the cells that need it.
b)A conformational change caused by low pH causes the oxygen to detach near the cells that need it.
c)Oxygen is displaced by carbon dioxide in the body.
D)Oxygen diffuses into or out of the blood following its concentration gradient.

Answer 1

Hemoglobin picks up oxygen in the lungs and releases it near body tissues that need it. In the capillaries, carbon dioxide enters the bloodstream and binds to hemoglobin. This process allows for the exchange of oxygen and carbon dioxide.

Step-by-step explanation:

In the lungs, hemoglobin picks up oxygen, which binds to the iron ions, forming oxyhemoglobin. The bright red, oxygenated hemoglobin travels to the body tissues, where it releases some of the oxygen molecules, becoming darker red deoxyhemoglobin, sometimes referred to as reduced hemoglobin. Oxygen release depends on the need for oxygen in the surrounding tissues, so hemoglobin rarely if ever leaves all of its oxygen behind. In the capillaries, carbon dioxide enters the bloodstream. About 76 percent dissolves in the plasma, some of it remaining as dissolved CO2, and the remainder forming bicarbonate ion. About 23–24 percent of it binds to the amino acids in hemoglobin, forming a molecule known as carbaminohemoglobin. From the capillaries, the hemoglobin carries carbon dioxide back to the lungs, where it releases it for exchange of oxygen.