YOUR BODY'S MICROSCOPIC "TRUCKS"

The Systemic and Pulmonary Circulation 

In the 17th century, doctors established that there are two types of blood circulation. In the systemic circulation, your body's microscopic "trucks," the red cells, set out from the heart to the body tissues. There they deliver oxygen and pick up refuse in the form of carbon dioxide. This process is called internal respiration.  The red cells then return to the heart. In pulmonary circulation, the "trucks" are sent to the lungs. There they unload refuse and reload with oxygen. So pulmonary circulation allows your body to breathe.

When There Aren't Enough Cells

Sometimes, there are fewer red blood cells than normal. This is the condition doctors call anemia.  It may have different causes, including (1) a defect in the production or maturation of red blood cells,  (2) an increase in their destruction, and (3) major bleeding. Anemia may also result from chronic inflammation or tumors.

Problems can result when there is either too much or too little iron in the blood. When there is too little iron, the red cells cannot mature normally.  As as result, the cells will be smaller and paler than usual. In many cases, treatment with iron corrects this defect.  Sometimes the level of iron in the blood is too high. This can occur when damaged red cells rupture, releasing iron  into the system. Progressively, all the body's  organs become poisoned.  The poisoning of the heart is particularly serious. Patients suffering from this condition almost always succumb to coronary cardiac insufficiency. 

Many books would be needed to explain all the work that blood cells do in your body, but it is evident that their marvelous complexity, only partially described here, exalts the wisdom of the One who designed and created life. Of the great and intelligent Creator, one of his ancient worshipers said: "By him, we have life and move and exist. -Acts 17:28. 

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