The process of blood clotting is called coagulation. Coagulation time is the length of time that it takes for blood to clot once it is drawn into a tube. Coagulation time is usually between 2 and 6 minutes.
Exercise 26.6 Materials:
Cotton ball soaked in alcohol Sterile disposable lancet Non-heparinized capillary tube Three cornered file
1. Scrub a finger with alcohol Stick the finger with a sterile lancet. Immediately after using the lancet; place it in the bio-hazard container. Any disposable object contaminated with blood should be placed into the bio-hazard container.
2. The non-heparinized capillary tube has a blue ring approximately 1/8"from one end of the tube. The end of the non-heparinized capillary tube closest to the blue line should be placed into a drop of blood on the end of your finger. Record the time to the second. Place the non-heparinized capillary tube into the blood at an angle slightly above horizontal. If bloodfails to fill the tube, lower the end away from the finger so that gravity will assist the capillary action. Fill the tube to the very end.
3. Exactly two minutes after blood first entered the non-heparinized capillary tube, use the three cornered file to make a small scratch (score) on the tube approximately 1/2"from the end of the tube farthest away from the blue line. At the two and one half minute mark, point the score mark away from you and apply gentle even pressure on either side of the score mark. Pressure may be applied by holding the non-heparinized tube with a thumb and index finger on either side of the score mark. Look for a thread of clotted blood between the two broken ends of the tube.
4. If no thread of clotted blood appears, immediately make another score mark on the non-heparinized capillary tube approximately 1/2"from the end of the tube farthest away from the blue line. At the three minute mark, apply gentle even pressure on either side of the score mark. Look for a thread of clotted blood between the two broken ends of the tube.
5. Continue this procedure at thirty second intervals until a thread of clotted blood appears between the two broken ends of the tube.
6. Place all sections of your non-heparinized capillary tube into the bio-hazard container.
7. Record your coagulation time below.
There are five major types of white blood cells: neutrophils, eosinophils, basophils, lymphocytes, and monocytes. Neutrophils have a nucleus with three to five lobes and fine pale light blue cytoplasmic granules (when properly stained). They make up 45% to 75% of the total white blood cell count. Eosinophils have a two lobed nucleus and red cytoplasmic granules. They make up 0% to 5% of the total white blood cell count. Basophils have an irregularly shaped nucleus and dark purple cytoplasmic granules that usually obscure the nucleus. They make up less than 2% of the total white blood cell count. Lymphocytes have a nucleus that is almost completely round with a thin layer of cytoplasm surrounding it. They make up 20% to 45% of the total white blood cell count. Monocytes have a kidney shaped nucleus. They make up 2% to 8% of the total white blood cell count.
Use your textbook to identify the blood cells shown in Figure 26.2.
Examine prepared microscope slides of blood that have been stained with Wright's stain. Identify and sketch the five major types of white blood cells.
Basophil Eosinophil Erythrocytes Lymphocyte Monocyte Neutrophil Thrombocytes
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This ebook provides an introductory explanation of the workings of the human body, with an effort to draw connections between the body systems and explain their interdependencies. A framework for the book is homeostasis and how the body maintains balance within each system. This is intended as a first introduction to physiology for a college-level course.