In this lab five blood tests will be performed: hematocrit determination, erythrocyte sedimentation rate, hemoglobin determination, blood typing, and total cholesterol determination. A “hematocrit refers to the percentage of red blood cells (RBC’s) in a sample of whole blood. Since the function of red blood cells is the transport of oxygen to the cells of the body, the higher the hematocrit, the more red blood cells are available to carry oxygen. ” In a normal, healthy male the value for males is 47% and in a normal, healthy female it is 42%.
A person with a lower than normal hematocrit would indicate they are anemic, and a higher than normal hematocrit would indicate polycythemia. “Anemia is a condition in which insufficient oxygen is transported to the body’s cells. There are many possible causes for anemia, including inadequare numbers of red blood cells, decreased amount of the oxygen-carrying pigment hemoglobin, and abnormal hemoglobin.
Polycythemia refers to a significant increase in red blood cells. Some causes for this increase in red blood cells are tumors in bone marrow, vigorous athletic training, and living in a place that is higher in altitude. To determine a hematocrit value a whole blood sample is put into microcapillary tube and spun in a special microhematocrit centrifuge. By doing this the blood sample will separate the blood cells from the blood plasma and there will be a “buffy coat” of white blood cells between the layer of blood plasma and red blood cell layer.
Then the hematocrit value can be determined “by measuring the height of the layer of red cells in millimeters and dividing that number by the height of the initial column of blood to obtain the percentage of red blood cells. In this experiment there will be six samples from six individuals, a healthy male who lives in Boston, a healthy female who lives in Boston, a healthy male who lives in Denver, a healthy female who lives in Denver, a male with aplastic anemia, and a female with iron-deficiency anemia.
What should be seen in these experiments is that they healthy male and female living in Boston should have an average hematocrit value, the healthy male and female living in Denver should have an elevated hematocrit, the male with aplastic anemia will most likely have a very low hematocrit, and the female with iron-deficiency anemia will also have a low hematocrit. “The erythrocyte sedimentation rate (ESR) measures the settling of red blood cells in a vertical, stationary tube of blood during one hour.
In a healthy person the red blood cells do not settle or settle very little over an hour, but “in some disease conditions, increased production of fibrinogen and immunoglobulins cause the red blood cells to clump together, stack up, and form a column”, which is called rouleaux formation. When the cells are grouped like this the red blood cells are heavier and they settle much faster. This test can be used to follow the progression of certain disease conditions like sickle cell anemia and inflammatory diseases like rheumatoid arthritis. When a condition worsens the ESR will increase and then when it improves the ESR will decrease.
Sometimes a female who is menstruating will develop anemia and in turn will have increase in ESR, as well as someone who has iron deficiency anemia. “ The ESR can be used to evaluate a patient with chest pains: the ESR is elevated in established myocardial infarction but normal in angina pectoris. ” In this experiment there will be six samples from six individuals, a healthy individual, a menstruating female, a person with sickle cell anemia, a person with iron-deficiency anemia, a person suffering from a myocardial infarction, and a person suffering from angina pectoris.
The healthy individual should have very little settling, a menstruating female will probably have an increased ESR, the individuals with sickle cell anemia, iron-deficiency anemia, and the person who is suffering a myocardial infarction, will all probably have an elevated ESR, and the individual suffering from angina pectoris will probably have a decreased ESR. Hemoglobin is a protein that is found in red blood cells, this protein is essential for the transportation of oxygen from the lungs to the rest of the cells in the body. “Anemia results when insufficient oxygen is carried in the blood.
A quantitative hemoglobin determination is useful for determining the classification and possible causes of anemia and gives useful information on some other disease conditions. ” Blood in a healthy individual contains approximately 12-18 grams of hemoglobin per 100 milliliters. “A healthy male has 13. 5 to 18 g/100 ml; a healthy female has 12 to 16 g/100 ml. ” In a person with polycythemia, congestive heart failure, or someone living in a high altitude location, will have increased hemoglobin.
To figure the hemoglobin content, a sample of blood will be stirred with a wooden stick which will rupture, or lyse, the cells. The intensity of the color of the lysed blood is a result of the amount of hemoglobin present. ” To determine the hemoglobin content of a sample, a hemoglobinometer will compare the samples color to standard values. “The hemoglobinometer transmits green light though the hemolyzed blood sample. The amount of light that passes through the sample is compared to standard color intensities. ” For this experiment, five samples will be evaluated, a healthy male, healthy female, a female with iron-deficiency anemia, a male with polycythemia, and a female Olympic athlete.
The healthy male and female should have an average hemoglobin value, probably around 12-18 g/100 ml, the female with iron-deficiency will most likely a low hemoglobin value, and the individual with polycythemia and the Olympic athlete will probably have a much higher hemoglobin value. Every person has a blood type and it is important to know a persons blood type before performing a blood transfusion in order to avoid mixing blood that is incompatible. Red blood cells, like all cells in the body, are surrounded by a plasma membrane. “The plasma membrane contains genetically determined glycoproteins, called antigens, that identify the cells.
On red blood cell membranes, these antigens are called agglutinogens. ” There are many different antigens that are present on red blood cell membranes, but the ABO and Rh antigens cause the most vigorous and potentially fatal transfusion reactions. “The ABO blood groups are determined by the presence or absence of two antigens: type A and type B. These antigens are genetically determined so a person has two copies (alleles) of the gene for these proteins. The presence of these antigens is due to a dominate gene, and their absence is due to a recessive gene.
The Rh factor is another genetically determined protein that may be present on red blood cell membranes. Antibodies to the Rh factor are not found preformed in the plasma. These antibodies are produced only after exposure to the Rh factor by persons who are Rh negative. ” Type A blood will have A antigens on red blood cells and anti-B antibodies present in the plasma. Type B blood will have B antigens on red blood cells and anti-A antibodies present in the plasma. Type AB blood will have A and B antigens on red blood cells and no antibodies present in the plasma.
Type O blood will have no antigens on red blood cells and anti-A and anti-B antibodies will be present in the plasma. In order to determine blood type, “separate drops of a blood sample are mixed with anti-sera containing antibodies to the types A and B antigens and antibodies to the Rh factor. An agglutination reaction (showing clumping) indicated the presence of the agglutination. ” This experiment will be testing six different samples of blood and determining the blood types of each sample. “Cholesterol is a lipid substance that is essential for life.
It is an important component of all cell membranes and is the basis for making steroid hormones, vitamin D, and bile salts. ” LDL, low density liproprotein, is a type of lipoprotein package that has been identified as a source of damage to the interior of arteries and can contribute to atherosclerosis, which is a buildup of plaque, in these blood vessels. “Less than 200 milligrams of total cholesterol per deciliter of blood is considered desirable. Between 200 and 239 mg/dl is considered borderline high cholesterol. Over 240 mg/dl is considered high blood cholesterol and is associated with increased risk of cardiovascular disease.
In testing for total blood cholesterol, four samples of blood will be mixed with enzymes that will produce a colored reaction with cholesterol. There is a color tester of standard values that will compare the color intensity of the samples to determine the cholesterol level. The color tester starts from a very light green, which is a low cholesterol level, and starts to get darker as the cholesterol level goes up. We would see a sample with a normal cholesterol level to be on the lighter green side and a sample with a high cholesterol level to be a much darker green.