Blood consists of an ample quantity of cells that fulfill different functions including oxygen transportation to the lungs and tissues, antibody formation, protecting body from infection and the other important missions. The life cycle of all cells has similar display, to a certain degree. However, the range of differences between cells remains more obvious. It can be obvious through the example of two kinds of cells: Red Blood Corpuscles (RBC) and White Blood Corpuscles (WBC), in other words – erythrocytes and leukocytes. As it comes clear from the names, the blood cells might be recognized due to their color identity.
Being of a red bright color, red cells are considered as the most abundant ones in the blood. Erythrocytes account approximately 40-45 percent of blood volume (Blood Basics, 2010). Hemoglobin, being a component of RBC absorbs oxygen from the lungs and releases it in the tissues during the blood run. The mission of white cells, however, is to protect the body from infection. The quantity of WBC is much fewer, when comparing with an abundance of red cells. They account for about 1 percent only of our blood. White cells produce special defensive proteins, called antibodies, which recognize dangerous elements in the body.
These two types of cells differ in their size and structure. Thus, a size of a red cell is approximately 6-8 ?m and it has a shape of biconcave disc “with a flattened center…both faces of the disc have shallow bowl-like indentations” (Blood Basics, 2010). An average level of erythrocytes should make four to six million per cubic mm, depending on sex, height and weight of a human. The lack of nucleus helps the red cell easily change shape. On the other hand, its flexibility provides damages of the cell membranes during the travel through the smallest blood vessels, thus limiting red cell’s lifetime to four months only.
Being irregular in shape, the white cells have a nucleus and an outer buffer coat. “Human blood contains about 5,000 to 10,000 leukocytes per cubic millimeter; their number increases in the presence of infection”(Blood Leukocytes, 2012). White blood cells measure 8 to 20 ?m in diameter. Their life span is very short and may come to few days. Depending on the quantity of nucleus in the cytoplasm of the cell, leukocytes maybe classified into two main groups: granulocytes and agranulocytes.
The function of granulocytes is to destroy bacteria, detect allergic intruders and fulfill an inflammatory response to infection. Agranulocytes additionally destroy organisms left behind work of the other cells. Some cells of this type “act as memory cells, ready for subsequent infection by the same organism” (Blood Leukocytes, 2012). Thus, an increase of WBCs in blood signifies the presence of infection. The low- level of red cells, in its turn, indicates anemia in a human. These two factors are of great importance for making a diagnosis.