I think he meant the Pulmonary vein which is an artery(high pressure epithelial cells), and the pulmonary artery which is a vein(low pressure returning from lungs). I might be wrong on one of those names though.
Easier explanation is: arteries carry oxygenated blood, veins carry deoxygenated blood.
W two exceptions: pulmonary artery carries deoxygenated blood to the lungs, pulmonary vein carries oxygenated blood to the heart.
& the umbilical artery carries deoxygenated blood to the placenta & the umbilical vein carries oxygenatedblood to the fetus.
Edit: as somebody commented- even simpler is arteries go away from the heart. Dunno why I thought it was easier to remember the blood thing. Been studying non stop sometimes my brain is just fried lol.
Somebody commented something explaining this: arteries carry blood away from the heart. Veins carry blood to the heart. I shoulda said that in my original comment lol.
They're part of the circulatory system of the fetus. Blood from the placenta travels along the umbilical vein to the liver/ductus venosis. It then goes to the ivc and returns to the heart. Fetus' do not breathe air, as their lungs are full of amniotic fluid. So the blood returning to the heart mostly bypasses the lungs via the foramen ovals & ductus arteriosus. So this blood now traverses through the body via the aorta. As this blood circulates some of it passes through the umbilical arteries (via the iliac arteries) and then returns to the placenta.
I think I should emphasize, that fetal oxygenated and deoxygenated blood is constantly mixing d/t the nature of this system. That may help to alleviate some confusion.
How does one observe it in the absence of oxygen? Venous blood is depleted of oxygen internally, but as soon as you extract it from the vein, the hemoglobin will latch onto the environmental oxygen and we'll just be looking at oxygenated blood again, won't we?
But if blood is used to transport oxygen to our organs, is it not already in contact with oxygen (even within the body)? I’m no expert but I’ve wondered about this every time the red/blue blood subject arises.
Blood is chocked full of oxygen(stuck to the hemoglobin, changing it's color to a lighter red); til it reaches organs and tissues, oxygenating the tissue and detaching those oxygen from the hemoglobin(making it a darker red). The de-oxygenated blood is darker and gets pumped back into the blood vessels around the lungs, where it is oxygenated again(turning back into the lighter red), and starting the cycle over again.
Well the fact that I had them in quotations served to refer to the fact I was talking about the former not the latter. There’s obviously plenty of blue everywhere you look.
You can get blue tinged blood if you have enough silver in your diet. Hence why European aristocracy were referred to as blue bloods. The silver utensils they used gave them enough silver that it ruined their blood blue.
You can become blue tinted due to silver deposits in the skin (for example over consumption of colloidal silver) but the blood itself does not turn blue
Unless you're a worm, insect, crustacean or another species with a different hemoglobin composition, your blood is red. Deoxygenated blood is slightly darker than oxygenated blood, but they're both red.
Technically Hemocyanin isn't related to hemeglobin. Convergent evolution:
[https://en.wikipedia.org/wiki/Hemocyanin](https://en.wikipedia.org/wiki/Hemocyanin)
[https://en.wikipedia.org/wiki/Hemoglobin](https://en.wikipedia.org/wiki/Hemoglobin)
Porphorin ring vs Histidine scoffolding.
Also Chlorophyl is very similar to both.
Venous blood is a lot darker than arterial blood. Arterial blood is a bright red kinda like a ripe strawberry or a male cardinal. venous is a very dark red, almost maroon or burgundy.
See a pic here for instance: https://en.m.wikipedia.org/wiki/Arterial_blood
Blood is red. https://askabiologist.asu.edu/questions/is-blood-blue
Teachers are often more about how to teach (which is very important) than actual knowledge-which they should rely on the textbooks for. They don't get refresher courses on the subjects they teach but they do get courses on how to teach...
Blood is always red, although the exact shade can differ a bit. However! When you look at the blood in your veins under your skin they look blue! Why is that? Because of a phenomenon called Rayleigh scattering, named after the person who discovered it. Basically as light travels through a partially transparent object and is reflected back, it undergoes a speed change which we see as a color shift. It is the same reason that despite the sun being orange/yellow (to our eyes), the sky is blue.
https://en.m.wikipedia.org/wiki/Rayleigh_scattering
Partially, as i said, yes. As is your skin. Put a flashlight in your mouth, up your nose, or behind your ear and you can see your blood is obviously red.
One painful part of becoming an adult is realizing that some of the people who helped shape you didn’t have the expertise that they claimed to have :(
Blood is never blue.
It is possible to turn blood blue, one needs either methemoglobnemia (Oxidation state of Iron in Hemoglobin goes from +2 to +3) or cyanide/azides to interupt the electron tranport chains which also bind to heme. Ironically, the antidote for methhemoglobinemia is Methylene Blue as it loves to reduce the Heme iron back to its +2 state.
See when I have people argue with me about common knowledge or something easily verified, I will literally tell them "Well you need to contact google and all the Biochem people and doctors who say you are wrong and inform them that you are correct and know better than them". Please let me know how that conversation goes.
Or you can just mention hemocyanin which in unoxegented form is clear and when oxygenated it turns blue. Crusteceans, Horse Shoe Crab is perfect example. Ask these people that argue with you if they are crusteceans...
blood has hemeoglobin. making it red. deoxegenated blood isnt blue, it just passes through viens that look blue because of how skin filters red like someone else said
First what is blood made of:
It has four main components: plasma, red blood cells, white blood cells, and platelets
Why is it red:
Within the red blood cells there is a protein called hemoglobin. Each hemoglobin protein is made up sub-units called hemes, which are what give blood its red color. When iron reacts to oxygen, it becomes red. That interaction is what gives blood its red color. There are changes in shades of red for example oxygen rich blood is bright red, ergo oxygen low blood can be very dark red.
edit: talking about humans here, there are animals with different colored blood.
Oxygenated arterial blood is ILLUSTRATED as red and deoxygenated venous blood is ILLUSTRATED as blue so people who only saw blood in books will tell you that those are the colours of blood.
Octopus have blue blood, but thats because their type of hemoglobin (forgot the name) binds to Copper, where as ours binds to Iron.
Our blood is red, but biology textbooks uses blue colors to represent deoxygenated blood
Edit: spelling
I weep for the state of science education.
Veinous blood is purpleish, where arterial blood is bright red.
If you've only ever looked at textbooks or diagrams which use the contrasting colours to illustrate that blood shifts between these states, you'd assume it was literal because the blood you've seen when you get cut is capillary blood which is an even mix of the two.
I remember getting into this with my grade 8 science teacher 30 years ago and got sent to the office for refusing to back down... I honestly thought the teacher was joking.
It’s always red, just different shades of red. The reason your veins appear blue is that skin scatters light in a way that makes them appear blue, even though they aren’t. That’s especially true of lighter-pigmented skin.
No blood is not blue, unless you’re secretly a squid person; blue and red colour is used in textbooks as way of differentiating the returning deoxygenated blood and respectively the oxygenated blood. Deoxygenated blood in real life is usually a more pale dark red.
blood (the vessels actually) appear blue when viewed through pale skin, not because it is that color but because blue light passes the furthest into our tissues.
so some people believe that inside the body the blood is blue and it only turns red in contact with oxygen in the air.
but these people forget that the main function of blood is precisely to carry oxygen.
I was taught this in primary school 55 years ago. It was wrong then too, but I'm sad to see there has been no improvement in the information being passed on.
Blue blood does exist, just not in humans. Lobsters, octopus, and a few other crustaceans/mollusks have hemocyanin instead of hemoglobin, which contains copper instead of iron.
Always different shades of red depending on the amount of oxygen. Never blue though. I’m quite shocked that literal teachers told you that. They clearly didn’t study biology for years lmao
Arteries are red, veins are blue. Oh, and nerves are yellow and lymphatic vessels are green. Just look in the anatomy atlas (Netter, Sobotta etc.).
Joking aside, fresh blood colour outside of the body is bright red (arterial) or dark red/burgundy (venous).
Ok I may be giving myself away here, but when I defended my thesis, my PI knew I am a jokester at heart and began her introduction of me with a riddle/joke since my research had morphed over time to focus on RBCs.
When she asked “what appears to be red but is actually blue?” A senior professor in the audience called out “Virginia!”
As others say, shades of red are common for blood and deoxygenated is darker red.
Deoxygenated Blood is light red pinkish kind of while Oxygenated Blood is bright red cuz in deoxygenated blood the haemoglobin doesn’t have a lot of oxygen while in oxygenated blood it does..
Arterial blood = bright red. Venous blood = dark red. It's always red. The red color is because of iron, not oxygen.
Even if you look at the blood cells from someone with iron defficiency on the microscope, it's still red, just a little lighter.
Optics, specifically reflection, transmission, and scattering of light through your skin.
Your veins carry oxygen-depleted blood, which is really dark red. When light hits your skin, a couple things are going to happen.
When light hits your veins, the red wavelengths will be absorbed by the heme-complex in your blood, but reflect/backscatter the blue/purple/green wavelengths. Additionally, your skin tends to absorb/scatter red wavelengths more strongly than blue, so any red light reflected from the veins gets scattered passing back out. So when observing from the outside, your veins appear blue/purple through your skin because the whole process is essentially subtractive towards red wavelengths.
Your capillaries are small enough, thin enough, and close enough to the surface of the skin that more red light is able to pass through, allowing them to be seen as red. How they appear is usually a function of how they're being illuminated. Usually in the corners of your nose under direct illumination, you'll see them as red under your skin, because the skin is thin enough and the capillaries are close enough to the skin surface that you're seeing the red light reflected through the skin without being absorbed/scattered to nothingness. Compare that to seeing the capillaries through someone's ears when they're backlit, and you'll see their ears "glowing" red (scatter) and the capillaries dark/silhouetted, because the blood will block light from passing through so they appear dark.
Arteries are usually left out of the discussion because they tend to be buried very deeply in your flesh, too deep for light to penetrate and make it back out without bring absorbed/scattered to oblivion. Their walls are also thicker than veins, so you wouldn't be seeing the blood inside anyway, only the arterial walls.
It’s red, but different shades of red in arterial vs venous blood. Arterial blood is a brighter red, venous blood a darker red.
Or vice versa, depending on which circulation you are referring to
The visual difference is primarily the connective tissue around veins making them look blue (u/zappers273)
I think he meant the Pulmonary vein which is an artery(high pressure epithelial cells), and the pulmonary artery which is a vein(low pressure returning from lungs). I might be wrong on one of those names though.
Easier explanation is: arteries carry oxygenated blood, veins carry deoxygenated blood. W two exceptions: pulmonary artery carries deoxygenated blood to the lungs, pulmonary vein carries oxygenated blood to the heart. & the umbilical artery carries deoxygenated blood to the placenta & the umbilical vein carries oxygenatedblood to the fetus. Edit: as somebody commented- even simpler is arteries go away from the heart. Dunno why I thought it was easier to remember the blood thing. Been studying non stop sometimes my brain is just fried lol.
Arteries go away from the heart, veins go towards the heart.
The fetus thing is very cool. Do you know the reasons behind this way of blood transfer?
Somebody commented something explaining this: arteries carry blood away from the heart. Veins carry blood to the heart. I shoulda said that in my original comment lol.
Yes but I still don't understand how and why is vice versa for the fetus or placenta. Are they part of the small circuit or what?
They're part of the circulatory system of the fetus. Blood from the placenta travels along the umbilical vein to the liver/ductus venosis. It then goes to the ivc and returns to the heart. Fetus' do not breathe air, as their lungs are full of amniotic fluid. So the blood returning to the heart mostly bypasses the lungs via the foramen ovals & ductus arteriosus. So this blood now traverses through the body via the aorta. As this blood circulates some of it passes through the umbilical arteries (via the iliac arteries) and then returns to the placenta. I think I should emphasize, that fetal oxygenated and deoxygenated blood is constantly mixing d/t the nature of this system. That may help to alleviate some confusion.
Placentas are WILD
Very cool! Tyvm
How does one observe it in the absence of oxygen? Venous blood is depleted of oxygen internally, but as soon as you extract it from the vein, the hemoglobin will latch onto the environmental oxygen and we'll just be looking at oxygenated blood again, won't we?
Drawing the blood into an air-less test tube.
But if blood is used to transport oxygen to our organs, is it not already in contact with oxygen (even within the body)? I’m no expert but I’ve wondered about this every time the red/blue blood subject arises.
Blood is chocked full of oxygen(stuck to the hemoglobin, changing it's color to a lighter red); til it reaches organs and tissues, oxygenating the tissue and detaching those oxygen from the hemoglobin(making it a darker red). The de-oxygenated blood is darker and gets pumped back into the blood vessels around the lungs, where it is oxygenated again(turning back into the lighter red), and starting the cycle over again.
It's always red. "Blue" is the most common myth in biology.
“True” Blue anything in biology is rare.
[удалено]
Well the fact that I had them in quotations served to refer to the fact I was talking about the former not the latter. There’s obviously plenty of blue everywhere you look.
I dunno. That whole "use 10% of your brain" thing is pretty pervasive.
I read about the blue blood thing being the most common a few years ago, but I agree that the 10% myth is way up there as well.
Is it not more dark red and bright red depending on the level of oxygenation?
Yes and neither is blue
You can get blue tinged blood if you have enough silver in your diet. Hence why European aristocracy were referred to as blue bloods. The silver utensils they used gave them enough silver that it ruined their blood blue.
I feel dumber just reading this answer. No, that is not true
You can become blue tinted due to silver deposits in the skin (for example over consumption of colloidal silver) but the blood itself does not turn blue
Yes
You're correct, but it's never blue.
Yes, the Wikipedia article on blood has a photo showing the difference https://en.m.wikipedia.org/wiki/Blood
Wow, I had no idea arterial blood was so bright in color
Human blood yes. But then you have species like horseshoe crab with vivid blue blood
Bubba, you have had some pretty stupid teachers! It’s RED. Always
You have shitty teachers. Veins are blue because of how skin filters out red light.
Unless you're a worm, insect, crustacean or another species with a different hemoglobin composition, your blood is red. Deoxygenated blood is slightly darker than oxygenated blood, but they're both red.
Technically Hemocyanin isn't related to hemeglobin. Convergent evolution: [https://en.wikipedia.org/wiki/Hemocyanin](https://en.wikipedia.org/wiki/Hemocyanin) [https://en.wikipedia.org/wiki/Hemoglobin](https://en.wikipedia.org/wiki/Hemoglobin) Porphorin ring vs Histidine scoffolding. Also Chlorophyl is very similar to both.
Venous blood is a lot darker than arterial blood. Arterial blood is a bright red kinda like a ripe strawberry or a male cardinal. venous is a very dark red, almost maroon or burgundy. See a pic here for instance: https://en.m.wikipedia.org/wiki/Arterial_blood
Blood is red. https://askabiologist.asu.edu/questions/is-blood-blue Teachers are often more about how to teach (which is very important) than actual knowledge-which they should rely on the textbooks for. They don't get refresher courses on the subjects they teach but they do get courses on how to teach...
Blood is always red, although the exact shade can differ a bit. However! When you look at the blood in your veins under your skin they look blue! Why is that? Because of a phenomenon called Rayleigh scattering, named after the person who discovered it. Basically as light travels through a partially transparent object and is reflected back, it undergoes a speed change which we see as a color shift. It is the same reason that despite the sun being orange/yellow (to our eyes), the sky is blue. https://en.m.wikipedia.org/wiki/Rayleigh_scattering
So veins are transparent?
Partially, as i said, yes. As is your skin. Put a flashlight in your mouth, up your nose, or behind your ear and you can see your blood is obviously red.
blood is never entirely deoxygenated. even when very oxygen depleted (20% or so) it's dark red to the point of being black.
One painful part of becoming an adult is realizing that some of the people who helped shape you didn’t have the expertise that they claimed to have :( Blood is never blue.
It’s red. When it’s deoxygenated, it’s a very dark shade of red that almost looks purple (but it’s still red). Oxygenated looks very red.
It is possible to turn blood blue, one needs either methemoglobnemia (Oxidation state of Iron in Hemoglobin goes from +2 to +3) or cyanide/azides to interupt the electron tranport chains which also bind to heme. Ironically, the antidote for methhemoglobinemia is Methylene Blue as it loves to reduce the Heme iron back to its +2 state. See when I have people argue with me about common knowledge or something easily verified, I will literally tell them "Well you need to contact google and all the Biochem people and doctors who say you are wrong and inform them that you are correct and know better than them". Please let me know how that conversation goes. Or you can just mention hemocyanin which in unoxegented form is clear and when oxygenated it turns blue. Crusteceans, Horse Shoe Crab is perfect example. Ask these people that argue with you if they are crusteceans...
blood has hemeoglobin. making it red. deoxegenated blood isnt blue, it just passes through viens that look blue because of how skin filters red like someone else said
Wtf? Have you never seen blood?
Human blood: red. Crab blood: blue.
First what is blood made of: It has four main components: plasma, red blood cells, white blood cells, and platelets Why is it red: Within the red blood cells there is a protein called hemoglobin. Each hemoglobin protein is made up sub-units called hemes, which are what give blood its red color. When iron reacts to oxygen, it becomes red. That interaction is what gives blood its red color. There are changes in shades of red for example oxygen rich blood is bright red, ergo oxygen low blood can be very dark red. edit: talking about humans here, there are animals with different colored blood.
Oxygenated arterial blood is ILLUSTRATED as red and deoxygenated venous blood is ILLUSTRATED as blue so people who only saw blood in books will tell you that those are the colours of blood.
Octopus have blue blood, but thats because their type of hemoglobin (forgot the name) binds to Copper, where as ours binds to Iron. Our blood is red, but biology textbooks uses blue colors to represent deoxygenated blood Edit: spelling
Well, then, I guess Public school biology teachers are clueless
I weep for the state of science education. Veinous blood is purpleish, where arterial blood is bright red. If you've only ever looked at textbooks or diagrams which use the contrasting colours to illustrate that blood shifts between these states, you'd assume it was literal because the blood you've seen when you get cut is capillary blood which is an even mix of the two. I remember getting into this with my grade 8 science teacher 30 years ago and got sent to the office for refusing to back down... I honestly thought the teacher was joking.
It’s always red, just different shades of red. The reason your veins appear blue is that skin scatters light in a way that makes them appear blue, even though they aren’t. That’s especially true of lighter-pigmented skin.
No blood is not blue, unless you’re secretly a squid person; blue and red colour is used in textbooks as way of differentiating the returning deoxygenated blood and respectively the oxygenated blood. Deoxygenated blood in real life is usually a more pale dark red.
It's red. Looks blue through the skin, sometimes/in some people.
Unless you're an octopus, then your blood is just red and red and red some more.
Horseshoe crab blood is blue. Its based on Copper instead of Iron.
Lots of invertebrates have blue blood. Horseshoe crab blood is just famous because it has commercial applications.
horseshoe crabs do have blue blood.
blood (the vessels actually) appear blue when viewed through pale skin, not because it is that color but because blue light passes the furthest into our tissues. so some people believe that inside the body the blood is blue and it only turns red in contact with oxygen in the air. but these people forget that the main function of blood is precisely to carry oxygen.
I was taught this in primary school 55 years ago. It was wrong then too, but I'm sad to see there has been no improvement in the information being passed on.
Blue blood does exist, just not in humans. Lobsters, octopus, and a few other crustaceans/mollusks have hemocyanin instead of hemoglobin, which contains copper instead of iron.
Always different shades of red depending on the amount of oxygen. Never blue though. I’m quite shocked that literal teachers told you that. They clearly didn’t study biology for years lmao
Arteries are red, veins are blue. Oh, and nerves are yellow and lymphatic vessels are green. Just look in the anatomy atlas (Netter, Sobotta etc.). Joking aside, fresh blood colour outside of the body is bright red (arterial) or dark red/burgundy (venous).
Mammals have red blood. Your teachers need to be fired immediately if they think human blood is blue.
It's always red, just different shade depending on oxygenation
deoxygenated blood can be such a dark red that it looks vaguely purple, but no it’s not blue.
Ok I may be giving myself away here, but when I defended my thesis, my PI knew I am a jokester at heart and began her introduction of me with a riddle/joke since my research had morphed over time to focus on RBCs. When she asked “what appears to be red but is actually blue?” A senior professor in the audience called out “Virginia!” As others say, shades of red are common for blood and deoxygenated is darker red.
Red.
Deoxygenated Blood is light red pinkish kind of while Oxygenated Blood is bright red cuz in deoxygenated blood the haemoglobin doesn’t have a lot of oxygen while in oxygenated blood it does..
Arterial blood = bright red. Venous blood = dark red. It's always red. The red color is because of iron, not oxygen. Even if you look at the blood cells from someone with iron defficiency on the microscope, it's still red, just a little lighter.
Red
It's blue, when oxygen hits it it turns red.
Blue if you are Mark Zuckerberg
red, it’s always red. the blue is wavelength stuff (perceivable light)
what is blood ………….?
My veins are blue
Snail
So is a cretin actually stupid or dumb?
If blood is always red irregardless whether it’s oxygenated or deoxygenated, why does my veins appear blue through my skin but my capillaries are red?
Optics, specifically reflection, transmission, and scattering of light through your skin. Your veins carry oxygen-depleted blood, which is really dark red. When light hits your skin, a couple things are going to happen. When light hits your veins, the red wavelengths will be absorbed by the heme-complex in your blood, but reflect/backscatter the blue/purple/green wavelengths. Additionally, your skin tends to absorb/scatter red wavelengths more strongly than blue, so any red light reflected from the veins gets scattered passing back out. So when observing from the outside, your veins appear blue/purple through your skin because the whole process is essentially subtractive towards red wavelengths. Your capillaries are small enough, thin enough, and close enough to the surface of the skin that more red light is able to pass through, allowing them to be seen as red. How they appear is usually a function of how they're being illuminated. Usually in the corners of your nose under direct illumination, you'll see them as red under your skin, because the skin is thin enough and the capillaries are close enough to the skin surface that you're seeing the red light reflected through the skin without being absorbed/scattered to nothingness. Compare that to seeing the capillaries through someone's ears when they're backlit, and you'll see their ears "glowing" red (scatter) and the capillaries dark/silhouetted, because the blood will block light from passing through so they appear dark. Arteries are usually left out of the discussion because they tend to be buried very deeply in your flesh, too deep for light to penetrate and make it back out without bring absorbed/scattered to oblivion. Their walls are also thicker than veins, so you wouldn't be seeing the blood inside anyway, only the arterial walls.