Why is blood red?

Answer:
The Hemoglobin molecule is red when attached to a oxygen molecule, it is not red when the O2 is not attached.

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It looks cool.

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Cells. Blood is accually blue when inside the body!

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Its actually blue, mixed with oxygen in the air turns it red.

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It's due to the heamoglobin molecules it contains. These are red coloured iron complexes.

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Well its actually blue but once the blood hits oxygen it turns red... and I have no idea why..lol.. :o)

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hemoglobin

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its actually blue, its red because when it touches the air it gets oxygenated, which turns it red.

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THINK I CARE?

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it is exposed to air when it is Red

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cause, its really blue,or purple but when it hits the air it turns that color.

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it' actually blue in our veins until oxygen hits it when we have a cut and it turns red

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Hemoglobin is what make the blood a red color.

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because thats what color it is, i dont think there is a reason

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something about oxidation or something--- blood is blue, which it why are vanes are blue but when the air touches it, it turns red.

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Blood is red because blood absorbs all the other colors of the visible spectrum, except for red. So red is transmitted instead. Get it.P.S. I took Biology, Chemistry, and Physics in college.

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red blood cellls are red and change the color to red

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blood isn't red its blue it turns red when it gets oxygen

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Because it contains Iron, which oxidizes (the same process as rusting!) when exposed to oxygen. Blood in the veins isn't red!

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When the iron in blood meets with oxygen, it makes it a red color. It's the same principle behind when iron rusts, it looks red.

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blood is red because of a pigment called haemoglobin in blood which imparts red colour

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I don't know how true it is but when I was little I was told blood was blue inside the body, and when it came to the surface it turned red due to oxygen

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so you can see it when you bleed. Its like a red light or tail lights on a car, when you see red, you stop. So when you bleed you see red, you stop, you put on a bandaid, or other care if its serious.

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Good question! When u find out why ... let me know.

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its not the blood thats red its the blood CELLS.

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red blood cells

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It is a chemical reaction between ingredients in blood and oxygen that turn it red. When the blood passes through the arteries it receives oxygen from the lungs and the blood turns red. The blood traveling back to the heart has been depleted of oxygen since that is one of the main purposes of blood, to bring oxygen to all of the cells. That is why veins are blue and arteries are red. Though there are "red blood" cells in the mix they are not red unless they are rich in oxygen. It is hemoglobin in the cells that actually carry the oxygen. I believe it is the reaction between oxygen and iron that makes the red color, like rust forming when iron is over exposed to air.

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Because it exposed to oxygen, but it is actually blue inside the body.

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Actually, human blood is blue. It only becomes red when it is exposed to oxygen.For the low down nitty gritty, check out the source link

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its actually blue. it turns red once it takes in oxygen.

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