Lab 3: Circulatory System Part I (Blood)

Dr. Kim Wilson

Exercise 29A – Blood

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Pg. 423 Read intro Figure 29A.1

Table 29A.1

Part 1: Blood Typing

PART 1: BLOOD TYPING 1. Students should organize themselves into groups of four. 2. Disinfect working area and wash your hands. 3. Obtain materials (listed below) and a clean paper towel on which to lay materials. Materials/Student: - 1 Blood Test Card - 1 Blue Mixing Stick (Anti A) - 1 Yellow Mixing Stick (Anti B) - 1 White Mixing Stick (Anti D) (Rh) - 1 Pair Latex Gloves 4. Decide within your group who will test each blood sample. Each student in the group should test a different blood sample. 5. Follow the instructions on the Blood Typing Handout omitting #'s 5, 6, 7, 14. and 15. 6. Discard all blood contaminated items in the Biobag. 7. Disinfect working area and wash your hands. 8. Answer related questions on the Questions Sheet.

Blood Typing

• • • • • • • Determined by presence or absence of specific antigens on the surface of red blood cells Classes of antigens: ▫ A antigens ▫ B antigens ▫ Rh antigens Specific antisera containing antibodies for the A, B, or Rh antigens is mixed with blood to determine blood type Whichever antiserum causes the blood to clump together indicates the blood type Major blood types: A, B, AB and O The Rh factor (Rhesus factor) may be present (Rh positive) or absent (Rh negative) in any of the major blood groups.

Reference pg. 434 and Table 29A.2

Part 2: Blood Smear

PART 2: PREPARED BLOOD SMEAR 1. Obtain a prepared blood smear slide. Draw and label several erthrocytes and platelets from the prepared slide on a piece of white drawing paper. Also, draw and label at least one neutrophil, lymphocyte, and monocyte. Use your textbook for reference. 2. Answer related questions on the Questions Sheet.

Blood Smear

• • • Composition Nonliving fluid matrix (plasma) (55% of blood) • 90% water; 8% proteins Living cells (formed elements) (45% of blood) ▫ Erythrocytes (red blood cells) ▫ Leukocytes (white blood cells) ▫ Platelets (blood clot formation) Source: http://lifesci.rutgers.edu/~babiarz/bloodtx.htm

Leukocytes (white blood cells)

• • Neutrophils (polymorphonuclear leukocytes; PMNs) ▫ 10 to 15 um diameter.

▫ Most abundant (40-70% of leukocytes) and usually have 2 to 5 nuclear lobes connected by fine filaments of chromatin ▫ Function as scavengers within extravascular tissue, destroying bacteria or other infectious organisms Eosinophils-- 10 to 15 um diameter ▫ About 2.0 to 4.0% of leukocytes ▫ Bilobate (two lobes) nucleus with a cytoplasm full of brightly stained eosinophilic (orange-red) specific granules ▫ Function specifically as phagocytes to destroy larvae of parasites that have invaded tissues

Leukocytes (white blood cells)

• • Basophils ▫ 10 to 15 um diameter ▫ Rare - 0.5 to 1.0% of leukocytes ▫ Nucleus consists of 2 to 3 lobes but is usually not as lobulated as neutrophils ▫ Cytoplasm contains dark purple specific granules ▫ Function: phagocytic, but function largely like mast cells Lymphocytes ▫ 9 to 14 um diameter ▫ About 20 25% of agranulocytes and may be small, medium or large in size. ▫ Nucleus is rounded or oval, and usually the same size as an erythrocyte ▫ Densely packed chromatin with no nucleus apparent ▫ Function: immune response

Leukocytes (white blood cells)

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Monocytes

▫ 12 to 20 um diameter ▫ About 3 8% of agranulocytes ▫ Large cell with lightly stained nucleus that often appears horseshoe or kidney shaped ▫ Chromatin appears lacy and nucleoli are usually not apparent ▫ Function: phagocytes (migrate to become macrophages)

Total White and Red Blood Cells

• • • Total WBC count – total number of white blood cells per unit volume of blood ▫ Leukocytosis – abnormally high WBC ▫ Leukopenia – low WBC ▫ Leukemia – malignant disorder of lymphoid tissues; uncontrolled proliferation of WBCs and reduction in RBCs Total RBC count – total number of red blood cells per unit volume of blood ▫ Polycythemia – increase in RBCs, which may result from bone marrow cancer or living in high altitudes ▫ Anemia – decrease in RBCs Differential WBC cell count – count 100 WBCs and classify them according to cell type

Post-Lab Questions

QUESTIONS SHEET (Include in your lab report) (Also include the blood smear drawing in your lab report.) PART 1: BLOOD TYPING 1. Discuss antigens and antibodies as they relate to blood types (both ABO and Rh systems). 2. Explain why agglutination occurs in the blood typing procedure. PART 2: PREPARED BLOOD SMEAR 1. What are the 3 kinds of formed elements? 2. What is the function of each type of formed element? (Include the major function of each type of WBC.) 3. Which formed element is the most numerous? 4. Define differential count and explain its importance.