Gotta be brainy for this one!?

Question

Everyone knows your blood is red, and your blood is inside your veins. Then why when you look at your veins are they blue and not red? Same with a bruise!

Answer 1

Not sure, but I think that has something to do with the cellular make up of our veins and ateries. I also think that veins are blue (the blood in these vessels are going back to the heart to get pumped thru the lungs for more oxygen) and the arteries are red. I could be wrong, though.

Answer 2

ok well, arteries bring oxygenated blood all over the body when it returns to the heart practically oxygenless it goes through your veins. B/c the veins are closer to the skins surface light reflects off of them and blue is the color you see. Your blood is NEVER blue. Remember that.

Btw, you can prove this b/c when blood is taken from you for testing, the blood in the tube is red. The tube has no oxygen in it (im not talking about the container im refering to the needle and its tube into the container) If blood is blue until it has oxygen you should see it turn back to red whne it reaches the container, but that never happens b/c your blood is ALWAYS RED

Apple84- I suggest you talk to your biology teacher b/c he is teaching you false information. I graduated High School in NY with a Regents Diploma and passed the regents with an 84%, second highest in my graduating class, and I can assure you blood is NEVER BLUE OR EVEN A SHADE OF BLUE.

Answer 3

Blood is pumped by the heart and constantly circulates through your body. When blood passes by the lungs, gas exchange occurs and a molecule called hemoglobin picks up free oxygen. Hemoglobin contains iron; blood with lots of oxygen-loaded hemoglobin is darker in color. This then goes throughout the body, all the cells take up the oxygen from the hemoglobin. Blood appears "blue" because of the loss of the hemoglobin. That blood must circulate back up to teh lungs to be "refilled" with oxygen and the circulation starts all over again.

Answer 4

bloode is not blue for one! ppl say when blood comes out of your body it hits oxygen of course it does. but the same is in your body bloods job is to carrie oxygen to your heart so there for blood isn't blue. the reason your veins are blue is because thats the couting of the viens. the reason why bruises are purple is bacause a bruise is bleeding under the skin. the blood is so far down that it is harder to see so it looks purple. tip: if you put a flah light to your hand you can see the bloode in your hand.

Answer 5

When your blood is well oxygenated, it appears bright red. The more oxygen it loses, the darker and bluer it becomes. So the bluish blood you see in your veins is deoxygenated blood travelling back to the heart. I imagine you are seeing the same thing with a bruise- deoxygenated blood rising to the surface of the skin.

Answer 6

Because your blood isn't really red. Your blood inside of the vein is blue. When you get a cut, the blood is then exposed to carbon dioxide which turns it to look that deep red.

Answer 7

our blood in the inside of our body is actually blue hence the
blue veins, when you cut your self and the bood gets into oxygen
it imeeadiently turns red

Answer 8

Your blood is actually blue inside your body when the oxygen hits it - it turns red. That's what I heard anyway. Maybe just a myth?

Answer 9

Blood is a bright red in its oxygenated form (i.e., leaving the lungs), when hemoglobin is bound to oxygen to form oxyhemoglobin. It's a dark red in its deoxygenated form (i.e., returning to the lungs), when hemoglobin is bound to carbon dioxide to form carboxyhemoglobin.


Veins appear blue because light, penetrating the skin, is absorbed and reflected back to the eye. Since only the higher energy wavelengths can do this (lower energy wavelengths just don't have the *oomph*), only higher energy wavelengths are seen. And higher energy wavelengths are what we call "blue."

Answer 10

Since the blood in our veins aren't exposed to oxygen, we see them as blue, as soo as it is exposed to oxygen, they're red.