Some teachers have no idea about things and still try to teach them. They aren’t different from other people there.

We were taught a lot of stupid shit in elementary school, because the teacher was a crank and proud of it. I remember vividly how he tried to explain the density anomaly of water (to ten year olds) by saying that atoms in solid objects move faster than in liquids and therefore need more space. I didn’t believe one word of it.

where was your school?

Everyone here slamming you for asking, but I’m just now learning from this thread that that’s not true.

Your school was beyond garbage. In my school they explained to me how hemoglobin works and why it’s red. (it’s because of Iron atom that captures specific wavelengths)

I never heard that while growing up, and would have thought that anyone who believed it was a dumbass. Ever see blue blood? No. Case closed.

Then I grew up, and found out that some people believe it, even as adults. Truly dumbasses.

You had some dumbass teachers.

Did you go to school during a period of time where there wasn’t access to information on the Internet? Old wives’ tales had more legs back in the day because you’d have to visit a library and open a card catalog to disprove them.

If your school taught you that it was a shitty school.

“We” weren’t because we had competent teachers. I do not know a single soul who was taught nonsense like this.

I think most people that think they were taught this in school actually just heard it a lot from random friends and acquaintances, as I did. I heard this all the time but never from a scholarly authority.

YMMV, of course.

I always understood that as like, a visual aid. So illustrations of red blood shows it’s carrying oxygen and the blue blood shows it has lost the oxygen, without delving into the molecules and how they gain and lose electrons.

Hypoxemia, hypo meaning underneath, ox meaning oxygen, and emia meaning presence in blood

Afaik, nobody knows where/when the myth started because it started organically, rather than being something like bumblebees not being aerodynamically sound, where there was poorly explained information that got spread from that point.

The most popular theory of the origin is that since veins look blue, and thus were drawn as such in anatomy illustrations, the idea got spread through wide ranging multi point origins. I’ve seen people argue for the veins looking blue as the genesis, with the idea being that someone asked why blue veins ran red when cut. But I’ve seen it argued that it wasn’t until the illustrations came along and faulty information was needed to explain that that it spread far enough to actually be taught by people that should have known better (like some folks, I ran into the idea in jr high, knew it was wrong because of family with medical training, and got in trouble for trying to say so).

But I have looked a few times over the years to see if I could run down a definitive origin story, and never have. Mind you, me looking involved searching for articles about it, rather than trying to run down historical references direct because I don’t have that kind of access.

I wasn’t taught that in school.

You were taught by a science teacher with no science background who didn’t read the book. That often happens in districts that underfund their schools.

I was definitely told this as a kid, but I don’t remember being taught it in school.

It’s completely possible a Latin teacher or a history teacher told me too but it wasn’t a part of the curriculum.