Thirty-three percent of an RBC is hemoglobin. The normal concentration of hemoglobin in blood is 15.5 grams per deciliter of blood in men, and 14 grams per deciliter of blood in women. (A deciliter is 100 milliliters, or one-tenth of a liter.)
Besides carrying oxygen to the cells of the body, the RBCs help to remove carbon dioxide (CO 2 ) from the body. Carbon dioxide is formed in the cells as a byproduct of many chemical reactions. It enters the blood in the capillaries and is brought back to the lungs and released there and then exhaled as we breathe. RBCs contain an enzyme called carbonic anhydrase which helps the reaction of carbon dioxide (CO 2 ) and water (H 2 O) to occur 5,000 times faster. Carbonic acid is formed, which then separates into hydrogen ions and bicarbonate ions:
carbon dioxide + water ==> carbonic acid + hydrogen ion + bicarbonate ion
The hydrogen ions then combine with hemoglobin and the bicarbonate ions go into the plasma. Seventy percent of the CO 2 is removed in this way. Seven percent of the CO 2 is dissolved in the plasma. The remaining 23 percent of the CO 2 combines directly with hemoglobin and then is released into the lungs.
White Blood Cells
White blood cells (WBCs), or leukocytes , are a part of the immune system and help our bodies fight infection. They circulate in the blood so that they can be transported to an area where an infection has developed. In a normal adult body there are 4,000 to 10,000 (average 7,000) WBCs per microliter of blood. When the number of WBCs in your blood increases, this is a sign of an infection somewhere in your body.
Here are the six main types of WBCs and the average percentage of each type in the blood:
Neutrophils - 58 percent
Eosinophils - 2 percent
Basophils - 1 percent
Bands - 3 percent
Monocytes - 4 percent
Lymphocytes - 4 percent