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Originally Posted by candidguy
TS:
You'll never encounter such a question on your paper. Rest assured.
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Well, I have no idea if this question is expected in paper. But science is a subject which needs a conceptual understanding. There are many things in science which you need to understand the actual concept of. I asked the question about pulmonary vessels with the same thought. Thanks for your participation candidguy.
Quote:
Originally Posted by Asad Shafiq
These vessels are 'defined' as those that carry blood to the heart and those that carry blood away from the heart. Their general characteristics include that arteries generally carry oxygenated blood and veins generally carry deoxygenated blood , with the exception of the pulmonary artery and veins. The reversal of function is not an exception to their definition but an exception to their characteristics. You mentioned it being an exception to the definition. It's a minute difference and probably doesn't even matter but i just wanted to clear the concepts of the the person making the enquiry.
An earlier typo may have made my answer somewhat hazy, i typed in 'now' instead of 'not'. Quote correction " The pulmonary artery carries deoxygenated blood away from the heart to the lungs and the pulmonary vein returns oxygenated blood to the heart from the lungs. Generally, arteries carry oxygenated blood and veins carry deoxygenated blood but that is 'NOT' how they're defined.
Again, it's a minor difference but i wanted the person asking to have a clear concept of it.
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Thanks a lot for making my concept clear. Here is what I understand why these vessels have twisted names:
Generally arteries carry blood away from heart to all parts of body and veins carry blood from lungs to heart. But in case of pulmonary vessels the situation is reverse.
Deoxygenated blood enters heart's right auricle from upper and lower parts of body through veins and then it flows into right ventricle through a valve. When the ventricle contracts, the de-oxygenated blood is pumped out of heart to lungs for re-oxygenation.
Pulmonary artery is an artery because it is a vessel coming from your heart.
Once the blood reaches lungs, it is reoxygenated and carried to heart through pulmonary vein. It opens into left auricle and then flows into left ventricle through a valve. Then, blood is pumped out of heart as the result of contraction of left ventricle and supplied to all parts of body.
The pulmonary vein is a vein simply because it is a vessel returning to your heart.
So, both pulmonary artery and pulmonary should not be understood in terms of oxygenation status, but rather in terms of blood flow in relation to heart.
I have just viewed a flow diagram which further clarifies the matter. I knew about the said vessels in crude terms before the discussion.
Thanks for contributing to my knowledge Asad Shafiq.
Regards