to think deoxygenated blood is blue?

[MountainMert]

So, I know blood is red but...
When I was at school, on diagrams, the oxygenated blood was coloured in blue to show it was oxygenated and the deoxygenated blood was red. This made sense to me because there's oxygen in water and water's blue.
DH is a science teacher and he's just told me that the diagrams now are the other way around. Oxygenated blood is red and deoxygenated is blue. This makes no sense to me.
Am I imagining that it was the other way around or did they change it?

Googling would suggest you are still right.

I remember it the opposite way to you, sorry! You know eater isn't blue actually either, right? it's just reflecting the sky...

Your DH is correct. Oxygenated blood is red which is caused when oxygen mixes with haemoglobin

No. It's just a darker red.

@CastleCrasher

I remember it the opposite way to you, sorry! You know eater isn't blue actually either, right? it's just reflecting the sky...

I'm 99.9% sure that water is actually blue.

I’ve never seen a diagram where oxygenated blood is blue. Deoxygenated blood is carried in veins which look blue so the diagrams have always had blue representing deoxygenated blood haven’t they?

Oh I’ve misread your OP!

Oxygenated was always red, I think, sorry.

Arterial blood is redder than venous blood if you’re bleeding, too. As a PP says, it’s the haemogoblins mixing with oxygen that make it red.

To clarify, I am talking about the way it is coloured ON DIAGRAMS not the colour of the actual blood.

I think you've always had it backwards. Oxygenated blood is (and arteries are) coloured red on diagrams, deoxygenated blood (and veins) blue. I went to school in the 1980s and pretty sure it was ever thus.
Deoxygenated blood looks darker in practice - ie blue- and arterial blood bright red.

I have done Anatomy & Physiology over the last two years for my college course and the deoxygenated blood route was always blue and the oxygenated red.

On the diagrams oxygenated was always red.

I've never seen a diagram with oxygenated blood shown as blue. Ever. Not at school, college, medical school, or in 20 plus years as a doctor. Oxygenated blood is bright red. Deoxygenated blood is darker red. Hypoxic people look blue.

Oh, and water looks blue because it's reflecting the sky.

Yeah the diagrams show the deoxygenated blood as blue but I had always assumed it was all red because you get a blood test from a vein and its still red?

This is like the Walkers crisps thing all over again. I'm definitely going insane. I thought Cheese and Onion used to be green too. Maybe I'm colourblind?

I've never seen diagrams showing oxygenated blood is blue. I've taught biology for 14 years and every diagram I've seen, used or drawn shows oxygenated blood as red.

I remember oxygenated as being red. It made sense to me as it would have been the most red in real life.

Smiths crisps always have cheese and onion as green (eg Square crisps) but Walkers always do it blue. You're not wrong about that

But what year did Nelson Mandela die?

@MountainMert

This is like the Walkers crisps thing all over again. I'm definitely going insane. I thought Cheese and Onion used to be green too. Maybe I'm colourblind?

You've mixed up the bloods. But you aren't wrong with the crisps - back in the days where we were buying Smith's, Golden Wonder and the like, Salt 'n' Vinegar was blue and Cheese & Onion Green. It was only when Walkers took over as the main brand on sale that the travesty that is confusing the South with covert Cheese and Onion that the packets changed colour.

No sorry, diagrams always red=oxy, blue=deoxy. You're incorrect, it's never been another way

Actual blood is never blue, it just looks that way through your skin because if the way light...oh, something or other...

However blood that had picked up oxygen from your lungs and is then pumped round your body through arteries is bright bright Red compared to the blood now relieved of oxygen going back to your heart in veins.

In diagrams the oxygenated blood travelling away from the heart is coloured red. The deoxygenated blood is coloured blue.

The touted theory used to be that deoxygenated blood was blue until it bled into the atmosphere where it absorbed oxygen and turned red.

You either didn’t pay attention at school or misremembered.

You are wrong about the blood but right about the crisps.

Oxygenated was always red on the diagrams and deoxygenated was blue.

And obviously water is clear (although I'm sure you were joking?)

they definitely changed the colour of the packaging of salt and vinegar and cheese and onion, in some brands at least. very confusing at the time.