Wednesday, March 25, 2009 Lecture

Wednesday’s lecture covered the cardiovascular system. We discussed the elements that blood is comprised of, covering the structure of an erythrocyte (red blood cell) and the various leukocytes (white blood cells) (i.e. neutrophil, eosinophil, basophil, lymphocytes, and monocytes). We also covered how to identify different leukocytes from one another and the functions of several of them. Red Blood Cells and White Blood Cells are both formed in the red bone marrow of the proximal epiphysis of long bones in adults. The structure of a RBC and the recycling of its parts were also covered. The process of blood clotting was overviewed, including the importance of clotting factor X and fibrinogen, which turns into solid fibrin and makes a web-like mesh to trap elements that form a clot. We covered the various blood types, the compatibility of blood types, and the anti-bodies each blood type has. The Rh factor was discussed as well as the importance of Rhogam shots for pregnant women. Finally, we studied heart models to determine the flow of blood in and out of the human heart.

Blood, a liquid connective tissue, is not only the most critical fluid in our body, but can also reveal disorders our body may have. The study and counting of different blood elements can indicate several disorders. A hematocrit shows the percentage of red blood cells in the blood, a low hematocrit can indicate anemia, while a high hematocrit can indicate dehydration or polycthemia (a bone marrow disorder). A high white blood cell count could indicate infection, inflammation, allergy, or stress. A low white blood cell count (leucopenia) could indicate infection or even cancer. A CBC, or complete blood count, performed by a medical specialist can evaluate both your white blood count (WBC) and red blood count (RBC) to determine and bodily disorders.