The Circulatory System for Dummies

muscle contractions, valves and blood circulation in veins

There weren’t a lot of rules back when anyone who wanted to could start publishing “freelance” articles for content farms. As a matter of fact, there weren’t any at all; at least as far as “extreme vetting” of the self-appointed experts’ content was concerned. You had journalism majors publishing on rocket science, rocket scientists publishing on cell biology, and cell biologists publishing on opera. Of course some of it was bull – what would you expect, especially from people pumping out as many articles in as short a time as possible? That’s how you end up with rubbish like what Imani Angulo published at Sciencing.com under the title, “What Three Things Help Push Blood Through Veins?”

According to Angulo, who we are pretty sure skipped anatomy class on the way to her degree in jazz music, those three things are

1. Heart
2. Valves
3. Capillaries

From her answer, which goes into excruciating detail about the circulatory system, it’s pretty clear that Imani didn’t understand the question. We say that because, according to Imani,

“The heart is the central mechanism of the circulatory system… The muscles of the heart contract and relax in coordination with each other, filling, pumping and emptying.” That’s nominally correct if one is speaking of the circulatory system in general – but the question was about veins. The general term “valves” could be part of the answer, except that Angulo intones that “The valves of the heart regulate the direction of blood flow within the heart…” Again, sort of true – but off-topic. In reality, there are one-way valves in most veins that prevent blood from flowing backward – but that’s not the same as the heart valves, Imani!

And as for capillary action? Again, not the point; which means that Angulo’s garbled description of blood flow through the capillaries is off-topic. In the real world, the pumping action of the heart is spent by the time blood gets to the veins, so veins need extra help. The three things that help push blood through the veins are the valves we mentioned before, peristalsis (muscle contractions of the vein walls) and the movement of the skeletal muscles. That last is why people who sit in the same position for a long time, e.g., in coach on an airplane, may suffer deep-vein thrombosis (DVT) – blood clots, often forming in the legs.

Not only did Angulo fail to understand the question – presumably because she’d forgotten the definition of “vein” from those long-ago fifth-grade science classes – but she also got part of what she did publish wrong. That’s more than enough for us to had Imani her second Dumbass of the Day award.

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