Why is blood red?
Blood is red because it is made up of a clear liquid (lymph) carrying large numbers of red blood cells, which carry oxygen to the body. Red blood cells are red due to hemoglobin, an iron-based protein. In the hemoglobin are four atoms of iron which can be in an oxidized state, i.e with oxygen attached (making it red), or in a non-oxidized state (when it is dark red-blue or maroon color).
Blood is pumped through the lungs, where it is oxygenated. Then it travels around the body to where the oxygen is required. When the oxygen is used up, the hemoglobin is routed back via the veins, and then back through the lungs again.
When arterial blood leaves the lungs to circulate through the body, it has just a little bit more oxygen in it than does venous blood. The reason it appears bright red is that the combination of iron, oxygen, and hemoglobin absorbs higher energy wavelength light (blue and green) which leaves the red wavelengths available for our eyes to sense.
The venous blood is never blue; it is a darker color of red than arterial blood, not blue. The color is a burgundy red or maroon color. Blood is bright red in the arteries and dark red in the veins. The reason venous blood is a darker red can be partially attributed to the slightly less oxygen in the blood in the veins. But its color change is more due to the "waste" it carries away from the body tissues and back to the kidneys for filtering and elimination. This "waste" darkens the red color of the blood (think of it as a little like dirty dish water).
Although a popular belief, being in contact with air does not cause venous blood to instantly oxygenate and turn red. It is red outside the body because it is red inside the body as well. When you look at unopened veins inside the body, in endoscopy, for example, they are a dark red color.
The blue appearance of the veins that you see when looking at them through the skin is not caused by blue venous blood. As explained, that is always red. The blue appearance is caused by a reflective factor of the skin itself. It is an optical property of the reflection of light off light colored skin and the difference in that reflection from the veins under the skin (but near the surface). That reflective process is complex, but the blue-looking veins are mostly all about the skin and reflection.
If arteries were not too deep to be visible through the skin, then they, too, would have a blueish appearance, the same as the veins for the same reasons.
Blood contains red blood cells. Red blood cells don't contain blood. Blood does not enter the red blood cell. Read More
blood has red blood cells (thrombocytes)... they colored the blood red.. Read More
oxygenated blood, or arterial blood, is bright red. deoxygenated blood, or venous blood, is dark red. Read More
None - red blood cells are also called red blood corpuscles. Read More
Yes, reptiles have red blood. The red color is caused by hemoglobin in the red blood cells. Read More
and a red blood cell or in a red blood cell? if its in a red blood cell i would say haemoglobin Read More
As the name says, red blood cells are found in the blood. If there is blood there, there is red blood cells. Read More
Oxygenated blood is bright red and deoxygenated blood is darker red. Read More
The red pigment is red blood cells is created by a blood protein called Hemoglobin Read More
Is your blood truly yellow but red blood overtakes the color and is an illusion that your blood is red but not?
your blood is purple but turns red when it meets with oxygen Read More
Oxygenated blood is red. This is why when you bleed, the blood emerges red. Oxygenated or, Oxygen rich, blood is bright red. De-Oxygenated or, Oxygen poor, blood is dark red. Read More
As we all now that red blood cells are important.If there's no red blood cells in the blood we die because the red blood cells carry the oxygen as we breath. Read More
Haemoglobin is the red pigment in red blood cells. Read More
The protein hemoglobin, found in the red blood cells, is what makes blood red. Read More
They don't have red blood. They don't have hemoglobin, the substance which makes a mammal's blood red. Read More
The red color of blood is caused by a red compound, oxyhemoglobin. Read More
Human blood is always red due to the presence of iron in red blood cells. Crustaceans have blue blood as their blood is copper-based. Read More
I'm afraid that this question may have confused you, as Red Blood Cells do not actually carry any Blood at all. This is because Blood is comprised of Red Blood Cells. The answer to your question is simply that Red Blood Cells carry no Blood, instead they make up Blood itself. Red Blood Cells Carry Oxygen. Read More
Red blood cells and white blood cells are produced in your red bone marrow. Read More
blood is red due to the blood cells that form blood. there are also white blood cells but are not seen because of the value of the red blood cells of a greater number. Read More
No. Your muscles do not produce the red blood cells. Red bone marrow produce the red blood cells. Read More
The red bone marrow produces most of the blood cells, including red blood cells. Read More
The old red blood cells get replaced by the newly formed red blood cells. Read More
The red blood cells make blood red. They have this color due to the hemoglobin molecule. Read More
Hemoglobin is the red pigment, or red color of Blood. Read More
Red, obviously!! Clue in the name RED blood cells! Read More
No your blood is not red until it hits oxygen, that is why your veins are not red. The above answer is incorrect. All blood is red but blood with oxygen is brighter red and blood lower in oxygen is darker red. All veins do not carry blood low in oxygen. Most do but not ones coming to the heart from the lungs. Read More
Most simply red blood cells are cells that carry oxygen from place to place and since they are in the blood and are red (blood would be clear without them) they are called red blood cells Read More
The copper in their blood gives their blood a bluish tint. It is much like how iron in our blood causes our blood to be red. Haemoglobin is a red pigment in blood that makes the blood red when it comes out into oxygen (that why when we bleed, our blood is red.) some animals do not have haemoglobin in blood, for example LOBSTERS! So this is why their blood is blue. Read More
why is it that the blood of an insect is not red Read More
blood is never blue but arterial blood lacking oxygen is darker... venous blood is dark red arterial blood is bright red capillary blood is brick red Read More