Laboratory Procedure #2

What is the primary function of white blood cells (WBCs)?

• Transport oxygen

• Fight infections and immunity

• Clot blood

• Carry nutrients

Which anticoagulant is preferred for WBC determination in automated analyzers?

• Heparin

• EDTA

• Sodium citrate

• Oxalate

What is the normal reference range for WBC count in adults?

• 3,500–10,500/µL

• 12,000–20,000/µL

• 1,000–3,000/µL

• 15,000–25,000/µL

What reagent is commonly used for manual WBC counting using a hemocytometer?

• Giemsa stain

• Turk’s solution

• Wright’s stain

• Saline

What is the primary function of Turk’s solution in WBC counting?

• Stains the nuclei of WBCs

• Hemolyzes red blood cells

• Preserves leukocytes

• All of the above

Which chamber is used for manual WBC counting?

• Neubauer hemocytometer

• Sedgewick-Rafter chamber

• Thoma chamber

• Counting slide

What magnification is typically used to count WBCs manually?

• 4x

• 10x

• 40x

• 100x

What formula is used to calculate the WBC count from a hemocytometer?

• Cells counted × dilution factor / area × depth

• Cells counted × depth / area × dilution factor

• Cells counted / dilution factor × area × depth

• Cells counted × area × dilution factor / depth

What is the dilution factor when using 0.5 mL of blood and 4.5 mL of diluent?

• 10

• 20

• 100

• 200

What is the total area counted in a Neubauer hemocytometer for WBC determination?

• 1 mm²

• 4 mm²

• 9 mm²

• 16 mm²