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Laboratory 11: Heart and Blood

Part 1: Blood Cell Types We will look at a stained blood smear to identify the blood cells types. You will need to search the entire slide to find all the blood cell types. A. Red blood cells. The most numerous blood cells are the erythrocytes, or red blood cells. Red blood cells contain hemoglobin which a protein that binds oxygen. Red blood cells are biconcave cells that lack a nucleus. B. White blood cells 1. Neutrophils are the most abundant white blood cells. They have a multi-lobed nucleus and the cytoplasm stains clear. 2. Eosinophils are large white blood cells, with bi-lobed nuclei and with pink staining granules in the cytoplasm 3. Basophils are large white blood cells, with bi-lobed nuclei and with purple staining granules in the cytoplasm 4. Monocytes have a U shaped nucleus and blue cytoplasm with no granules 5. Lymphocytes have a round nucleus that fills almost the entire cell. C. Platelets Platelets are fragments of megakaryocytes. The are small, purple cell fragments in the blood smear. Procedure 1: Identifying blood cells types Search the prepared blood smear slide and identify all the blood cells types listed above. Use your book (page 200) and handouts in this manual. Sketch each blood cell type.

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Part 2. Determine Blood type using a blood type kit Your blood type is determined by what type of proteins are coating your red blood cells. The type of protein you have is inherited. We use the A B O Blood Groups: Type A blood has type A antigen (protein) on the surface of the RBC. Type B blood has type B antigen on the surface of the RBC. Type AB blood has type A and B antigens on the surface of the RBC. Type O blood has no antigens on the surface of the RBC. We also have antibodies to proteins that are not normally found our bodies. If you have type B blood, then you have B proteins on your RBCs, but you do not have Type A proteins. But you will have antibodies to the type A proteins (anti A antibodies). If you come into contact with type A blood, your antibodies will attach themselves to the type A proteins and the blood cells will aggregate (stick together). Some of the type A blood cells may be lysed (broken open). There is also a blood protein referred to as type D or Rh factor. If you have the Rh factor protein on your blood cells you have “positive” blood. So you may be type A+, meaning that you have type A proteins and Rh proteins coating your blood. Rh factor antibodies can cause a problem during pregnancy because these antibodies are small enough to pass through the placenta, it is very rare that type A or B proteins will pass through the placenta. We will test blood types by treating a cell with the antibodies to see if there is a reaction. Procedure 2: Determining Blood Type Follow the direction in the blood type kit handout on the following pages. Part 3. Sheep’s Heart Dissection Each group will be given a sheep’s heart to dissect. Sheep’s hearts are very similar in size to human hearts. There are some differences in the architecture due to the fact that sheep are four-legged animals. The most notable difference is the presence and orientation of the anterior and posterior vena cava. Humans in contrast have superior and inferior vena cavas. Procedure 3: Sheep’s Heart Dissection Follow the directions in the Sheep Heart Dissection handout. There are gloves available to use while dissecting the heart. When you are finished, place your heart in the plastic bag near the sink. Wash your dissecting tray and equipment with soap and water, scrub

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the dissecting tools with a brush. Place the tools on the paper towel lined tray to dry and place the tray up-side down next to the sink. Wash your hands. Part 4: The path of the blood through the heart and the parts of the heart Using the cardio lab handout given in this manual, be able to describe the path of the blood through the heart, to the lungs, back to the heart then out to the body. On a heart model, be able to identify the following structures and know if the blood passing through that structure would be oxygen rich or oxygen poor. Superior and Inferior vena cava Right Atrium. Tricuspid AV valve Right Ventricle. Pulmonary SL valve Pulmonary Arteries Pulmonary veins Left Atrium. Mitral AV valve L Ventricle Aortic SL valve Aorta Coronary arteries and veins Septum Chordae tendineae Papillary muscles