Why is blood red?

Answer 1

The blood flowing through the arteries, capillaries, and veins of our bodies contains many different materials and cells, each with a different function. Plasma, the liquid portion of the blood, comprises more than half of the blood. Plasma is light yellow in color, and is thicker than water, because it contains many substances, in addition to the actual blood cells. These substances include proteins, antibodies that combat disease, fibrinogen, which helps blood clot, carbohydrates, fats, salts, and others.

Red blood cells, or corpuscles, encased in blood vessels, color the blood. Since there are about 35 trillion of these tiny, round, flat discs circulating in one's body at any one time, their sheer number necessarily lends their red color to the blood.

As the young red blood cell matures, and takes on an adult form in the marrow of the bone, it loses it's nucleus, and it increases its production of hemoglobin. Hemoglobin is the red pigment, or color of blood, and contains iron, combined with protein.

When blood passes through the lungs, oxygen piggybacks on the hemoglobin of the red cells. From there, the red cells carry the oxygen through the arteries and the capillaries to all other cells of the body. Carbon dioxide from the body cells returns to the lungs through the veins in the same manner, by attaching to the hemoglobin.

Red blood cells have a life expectancy of approximately four months, before they are broken up, primarily in the spleen, and are replaced by new red blood cells. New cells are continuously generated to replace the old cells that have past their prime, and have been destroyed to make room for the younger generation.

Answer 2

blood contains various types of cells, one of which is red blood cells. These cells contain a protein called haemoglobin which carries oxygen from the lungs to all the cells in the body (which need oxygen to survive). Haemoglobin contans iron, and its the iron-protein complex that makes the red cells red, which give blood its colour.
This is not a stupid question, there is a good reason for blood being red.

Answer 3

Blood contains many types of blood cells, such as White Blood Cells, Red Blood Cells and Platelets. In the blood one can find many RBC (Red Blood Cells) and a little WBC and platelets.
The RBC are used to carry oxygen from one place to another and so when it contains the oxygen it becomes red.

Answer 4

Color
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

Answer 5

having red blood cells

Answer 6

Haemoglobin has an iron atom (Fe) at its centre.

When oxygen is bound to Fe2+ in heme, all 6 d-electrons of the iron atom are forced into the three lower-energy t2g orbitals, where they must all be paired (see crystal field theory for diagram). This produces the “low-spin” state of oxyhemoglobin. The sharp high-energy of transition between the t2g and empty eg states of d-orbital electrons in oxyhemoglobin is responsible for the bright red color of the substance. When oxygen leaves, the Fe2+ is allowed to move out of the porphyrin ring plane, away from its five ligands toward the empty space formerly occupied by the O2, and in these circumstances eg orbital energies drop and t2g electrons move into them. This causes the iron atom to expand and increase its net spin, as d-orbitals become populated with unpaired electrons. In these circumstances, the absorption spectrum becomes broader, with smaller transition levels, producing the dark color of deoxyhemoglobin.

Answer 7

It is red because of our iron intake from food and because of the red blood cells which contain hemoglobin, the red pigment of the blood.

Answer 8

Blood is red because it is not green.

Answer 9

When the hemoglobin in blood is oxygenated, it is red in colour. I won't go in to the spectral colour issue and bore you. Thats why when we see our veins under our skin they appear blue because venous blood is unoxygenated.

Answer 10

iron get fixed to heamoglobin\ hbs gather in large sacs called RBCs.iron is blue.when in contact with oxygen,it appears in red,the reduced energy radiated by the combination of iron and oxygen. you see blood only through wound and something else when it come to contact with the air containing oxygen.it is because of the huge potential of heamoglobin to acsept oxygen in them and you will never see your purple blood under the veins.