Blood Physiology
... Because of this men have a greater demand of circulating O2 so they need more red blood cells and hemoglobin to carry the excess O2. List the major functions of the following leukocytes: Neutrophils: Neutrophils squeeze through the capillary walls and into infected tissue where they kill the invaders (e.g., bacteria) and then engulf the remnants by phagocytosis. Eosinophils: Eosinophils are cytotoxic, releasing the contents of their granules on the invader. Basophils: Basophils leave the blood and accumulate at the site of infection or other inflammation. There they discharge the contents of their granules, releasing histamine which increases the blood flow to the area and in other ways add to the inflammatory process. Lymphocytes: There are several kinds of lymphocytes (although they all look alike under the microscope), each with different functions to perform . The most common types of lymphocytes are B lymphocytes ("B cells") and T lymphocytes (“T cells”). B cells are responsible for making antibodies. There are several subsets of T cells. They include inflammatory T cells that recruit macrophages and neutrophils to the site of infection or other tissue damage, cytotoxic T lymphocytes (CTLs) that kill virus-infected and, perhaps, tumor cells and helper T cells that enhance the production of antibodies by B cells. Monocytes: Monocytes leave the blood and become macrophages. Macrophages are large, phagocytic cells that engulf foreign material (antigens) that enter the body and dead and dying cells of the body. Define the following terms: Leukemia: Cancer of white blood cells. Acute leukemias are characterized by the presence of "blasts," which are immature white blood cells. Large quantities of blasts generally overgrow the bone marrow, leaving very little space for normal bone marrow cells. This type generally requires immediate treatment. Chronic leukemias are those characterized by a large and uncontrolled growth of more mature white blood cells. These types of leukemias tend not to progress as rapidly, and treatment is often milder than that of acute leukemias. Leukocytosis: an increased white blood cell count, usually caused by the presence of an infection. Leukopenia: an abnormally low number of white blood cells in the circulating blood. Mononucleosis: an acute disease characterized by fever and swollen lymph nodes and an abnormal increase of mononuclear leucocytes or monocytes in the bloodstream; not highly contagious; some believe it can be transmitted by kissing Thrombocytopenia: an abnormally low number of thrombocytes (platelets); the condition may result in abnormal bleeding and bruising. The normal platelet range is 150,000-300,000 per millimeter of blood. Thrombocytopenia may be controlled by the administration of certain cytokines or by removal of the spleen. Hemophilia: an inherited bleeding disorder caused by low levels, or absence of, a blood protein that is essential for clotting; hemophilia A is caused by a lack of the blood clotting protein factor VIII; hemophilia B is caused by a deficiency of factor IX. Why is a person with type O blood called the “universal donor”? The ABO system of blood typing refers to a type of antigen present on the membrane of red blood cells. Each antigen has a complementary antibody. A person’s plasma contains the complimentary antibodies to the red cell antigens. Meaning a person with Blood type A has antigen A and antibody B. Complementary antigens and antibody react to form a blood clot or agglutination of the red cells. Type O blood is the universal donor because it has neither antigen or antibody type so it can be used to transfuse any type of blood. No reaction will occur because there are antibodies to react with the recipients antigens. Why is a person with type AB blood called the “universal recipient”? A person with type AB blood is the universal recipient because they have both antigens and antibodies in their blood stream. Not matter what type of antigen is introduced it will not react because it already exists in the recipients blood stream. Under what conditions in erythroblastosis fetalis possible? Why is the condition given this name? Erythroblastosis fetalis is possible when a Rh- mother is carrying an Rh+ child. It is given this name because when exposed the second time to the Rh+ blood type the mothers immune system will begin to attack the fetuses blood which will lead to the destruction of the fetus. What treatment can be given for erythroblastosis fetalis? It can be treated in utero (before birth) by medication or intrauterine transfusion. When the child is born, signs may include an enlarged liver and/or spleen, generalized edema (swelling, anasarca), jaundice, and anemia. After birth, depending on the severity, a transfusion may be performed. What is the difference between active and passive immunity? Naturally acquired active immunity occurs when the person is exposed to a live pathogen, develops the disease, and becomes immune as a result of the primary immune response. Artificially acquired active immunity can be induced by a vaccine, a substance that contains the antigen. A vaccine stimulates a primary response against the antigen without causing symptoms of the disease. Artificially acquired passive immunity is a short-term immunization by the injection of antibodies, such as gamma globulin, that are not produced by the recipient's cells. Naturally acquired passive immunity occurs during pregnancy, in which certain antibodies are passed from the maternal i...