Реферат: White Blood Cells Essay Research Paper White
White Blood Cells Essay, Research Paper
White Blood Cells
Bacteria exist everywhere in the environment and have continuous access to the body through the mouth, nose and pores of skin. Further more, many cells age and die daily and their remains must be removed, this is where the white blood cell plays its role.
According to this quotation, without white blood cells, also known as leukocytes, we would not be able to survive. White blood cells are our body’s number one defense against infections. They help keep us clean from foreign bacteria that enter our bodies. Statistics show that there are five to ten thousand white blood cells per micro liter of blood, however this number will increase during an illness. White blood cells can differ in many ways, such as, size, shape and staining traits. There are five different kinds of white blood cells that fall into two separate categories. One category is called, granular leukocytes, and the other is called agranular white cells.
There are three different types of granular leukocytes. Neutrophil is a phagocyte, produced in the bone marrow that ingests and destroys bacteria extremely fast. Neutrophil has a diameter, which is, about ten to twelve micrometers long. They make up about 60-70 percent of the total number of white blood cells in our body. Eosinphil is a type of white blood cell that secretes poisonous materials in order to kill parasites, allergies and phagocytosis of bacteria, which is when the cell takes in materials to eliminate them or move them from where they were. They make up about 2-4 percent of the total number of white blood cells in our body. These white blood cells are similar to Neutrophil because they attack bacteria by the immune system. This particular group of white blood cells is extremely important in my body, because they are prominent at sites of allergic reactions, such as anaphylaxis. The nucleus of Eosinphil is made of two lobes, and implanted in the cytoplasm are large, red-orange granules, and the diameter of them is on average about twelve to fifteen ?m. The third type of granular leukocytes is called, basophil. Basophil’s major function is, secretion. They tend to have a diameter of 12-15 ?m. These cells make up only about one percent of the total population of white blood cells, causing them to be much more difficult to detect. These cells secrete both histamine and heparin. Histamine draws blood into the damaged area, while heparin slows clotting so that more blood can enter the damaged area.
There are two different kinds of agranular white cells. One is called monocyte, and the other is called lymphocyte. The major function of monocyte is, phagocytosis. These cells more very quickly and are therefore able to consume bacteria and dead tissue at a fast rate. Monocytes have an average diameter of, 12-17 ?m, and they make up about 3-8 percent of our leukocyte’s population. Lymphocytes, major function are immunity. There are many different forms of lymphocytes, and all of the different forms have different functions. B-lymphocytes produce, plasma cells, which form antibodies to (humeral immune response), T-lymphocytes produce, suppressor cells, helper cells, and cytotoxic, killer cells. Lymphocytes have a diameter of about 8-18 ?m. In general leukocytes, “either clear away dead cells from the body, or destroy specific bacteria, viruses, and other agents of disease.”
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