What color is human blood?
956109
In humans and other hemoglobin-using creatures, oxygenated blood is bright red. This is due to oxygenated iron in the red blood cells. Deoxygenated blood is a darker shade of red, which can be seen during blood donation and when venous blood samples are taken. However, due to an optical effect caused by the way in which light penetrates through the skin, veins typically appear blue in color. This has led to a common misconception that venous blood is blue before it is exposed to air. Another reason for this misconception is that medical charts always show venous blood as blue in order to distinguish it from arterial blood which is depicted as red on the same chart.
665935
Red blood cells(eritrocyte)-Hemoglobin\n\nWhite blood cells(leucocyte)-\n1. granulocyte-lymphatic vessels and monocyte\n2. agragranulocyte- neutrophil,basophil,eosinophil\n\nPlatelets(thrombocytes)
406086
Males have up to 6 units of blood and females have up 5 units of blood, but I think that is all humans, not just Americans. HA HA HA HA !!
637537
It's actually a bluish-green.  Look at your veins that come to the surface of your skin.  Blood only turns red when it comes into contact with oxygen.
1053811
Red, just about any warm blooded mammal has haemoglobin that has an iron base and accounts for the red colour. Difference in colour only occurs in animals such as insects or spiders because they have a different base, spiders have a copper base.
587615
oxygenated blood is red. deoxygenate blood is blue, you always bleed red because blood pulls the oxygen out of the air the same way  it would in your lungs, and yes it happens to everyone
156204
I don't believe that guy called her a moron for giving the right answer. Yes blood without oxygen is blue but it may appear green due to you looking at it through your skin. I'm sure you've seen someone with blue lines on their body. When blood becomes oxygenated...the Fe is pulled to the center of the heme ring. It's actually this conformational change that produces the red color. Not rust. Also to comment. The Fe is contained within the porphyrin ring but not in a flat structure. It is partially off center and is pulled more equally within the ring structure with the addition of oxygen. If you looked it up you'd know I wasn't making **** up. Although i do apologize for the blue comment. But we see blue because of the absorption of light at the surface of our skin. At least while the blood is stil in circulation. You need to be less critical. Yes all of them are red but to the naked eye under the skin they clearly appear blue. It's not total "bullocks" for someone to assume such. The intelligent should learn to be teachers not arrogant tactless shrews.
65667
The color of blood is blue.
473152
red blood cells are circular cells that transport oxygen throughout the body. white blood cells are part of the immune system and fight infection and foriegn objects that enter the body. plasma is the liquid part of blood, and platelets are the part of the blood that cause clotting.
500857
Basically there are numerous cells in the body composing of white blood cell and red blood cell
230652
color of skin\ngender
525270
They have blue blood, which is a result of its high content in copper-based hemocyanin instead of the iron-based hemoglobin which is red.
539773
No, this is a very common myth. Blood is always red. When in an oxygen poor stage it assumes a red color that is not as intense as the red of the oxygen rich stage. The blue color comes from looking at your deoxygenated blood through layers of skin as well as the veins.
883967
Blood is about 7% of the human body weight, so the average adult has a blood volume of about 5 litres, of which 2.7-3 litres is plasma. Human blood density is around 1060 kg/m³. The combined surface area of all the red cells in the human body would be roughly 2,000 times as great as the body's exterior surface
24470
Blood is blue when it's not oxygenated, for instance when it's in veins, which return blood to the heart to be refilled with oxygen after it's been used.  Veins are those blue lines you can see under people's skin-- that's blood.  Blood in arteries (which are usually lower than veins and thus not visible through people's skin) is red. \n \nSo, to summarize, red oxygenated blood leaves the heart and goes around to the rest of your body, where it fuels your muscles and organs.  They use up the oxygen, turning it blue.  Via the veins-- those little blue lines that are visible sometimes in people's neck or hands-- the blood returns to be filled again with oxygen. \n \nWhen you cut yourself, the blood becomes oxygenated as soon as it hits the air, so that's why regardless of where it comes from it's always red by the time you see it. \n \n<3
1174899
Green \n\nor maybe blue
686805
In humans and other hemoglobin-using creatures, oxygenated blood is a bright red in its color. Deoxygenated blood is a darker shade of red, which can be seen during blood donation and when venous blood samples are taken. However, due to an optical effect caused by the way in which light penetrates through the skin, veins typically appear blue in color. This has led to a common misconception that before venous blood is exposed to air it is blue.