Video Transcript
What is the primary purpose of the
pulmonary circulation pathway? (A) To transport blood between the
heart and the lungs. (B) To transport blood between the
heart and the rest of the body. (C) To transport glucose and amino
acids to the liver. Or (D) to transport blood to the
heart to be oxygenated.
The human circulatory system is
composed of a heart, which functions as a central pump, and a complex network of
blood vessels. These blood vessels transport
blood, which delivers oxygen and essential nutrients to the organs and carries away
carbon dioxide and other waste products.
There are two main circulation
pathways that make up the body’s circulatory system: the systemic circulation and
the pulmonary circulation. Together, these two pathways
function to keep blood flowing to and from the various organs of the body. As this question asks us to
identify the primary purpose of the pulmonary circulation pathway, let’s investigate
the key differences between the two.
The word “systemic” refers to the
whole body, as the systemic circulation pathway is responsible for delivering
oxygenated blood from the heart to the brain, liver, intestines, and almost all of
the other organs in the body. Oxygen is taken up from the blood
by the cells of the organs, and the blood collects their carbon dioxide and waste
products. This blood is now said to be
deoxygenated and is carried back to the heart.
So where does the blood get the
oxygen it needs to deliver to the organs? And what happens to the carbon
dioxide in deoxygenated blood? Well, this is the function of the
pulmonary circulation pathway. This pathway carries deoxygenated
blood from the heart to the lungs. This is easy to remember, since the
word “pulmonary” refers to the lungs. This carbon dioxide is exhaled from
the body, and inhaled oxygen enters the bloodstream via the lungs. The oxygenated blood is carried
back to the heart, ready to be pumped through the systemic circulation pathway.
Now that we have reviewed the two
main components of the circulatory system, we can answer our question correctly. The primary purpose of the
pulmonary circulation pathway is (A), to transport blood between the heart and the
lungs.
