blood lab#2

Blood Lab #2:  ABO/Rh Blood Typing       
Purpose: Blood spatter was left at a crime scene. Investigators believe the perpetrator was cut on the
weapon and left his/her blood at the scene.Four persons of interest may have been at the crime scene. 
In this experiment, the  technique to identify an individuals using ABO/Rh blood typing  will be used to 
determine the identity of the suspect who left his/her blood at the scene.    
Procedure Part I: (copy the data table into your notebook)  
1. Using a marker, label the  5 blood typing spot plates for each individual   
suspect as W, X, Y, and Z. Add one more plate as the Crime Scene (CS)  
2. Add 3 drops of Person W's blood in each of the 3 wells on the spot plate.  
           
3. Add 3 drops of anti-A Sera to the A well.     
           
4. Use a tooth pick to gently stir the 6 drops . (do not stir hard or it will scratch the plate!).
  Throw away used tooth pick!!!      
5. Observe the spot plate against a white background to note any clumping.   
           
6. Record you results in the data table as "clumping" or "no result".  
           
7. Add 3 drops of anti-B Sera to the B well.     
           
8. Use a tooth pick to gently stir the 6 drops . (do not stir hard or it will scratch the plate!).
  Throw away used tooth pick!!!      
9. Observe the spot plate against a white background to note any clumping.   
           
10. Record you results in the data table as "clumping" or "no result".  
           
11. Add 3 drops of anti-Rh Sera to the Rh well.     
           
12. Use a tooth pick to gently stir the 6 drops . (do not stir hard or it will scratch the plate!).
  Throw away used tooth pick!!!      
13. Observe the spot plate against a white background to note any clumping.   
           
14. Record you results in the data table as "clumping" or "no result".  
           
15. REPEAT PROCEDURES 2- 14 USING PERSONS X, Y AND Z.  
             
Procedure part II: IDENTIFICATION OF THE CRIME SCENE BLOOD SWATCH.
           
1. Obtain a the crime scene bindle from the crime lab manager.    
2. Record your bindle number in your data table, open the bindle and remove the swatch 
  using the tweezers.        
3. Use a pair of scissors to cut the swatch into 4 small squares- place them back into the 
  bindle using the tweezers.        
4. Place 1 small square swatch into the 3 wells on the spot plate labeled CS.  
5. Add 3 drops of distilled water on top of the swatch. Let stand for 1 minute as the blood 
  dissolves into the water.        
6. REPEAT procedures 3-14 from Part I.    
CLEAN UP : Rinse the spot plates into the wash bin using the distilled water bottles.  
Return the dried spot plates to the blood typing kits.    
Data Table : ABO/Rh Blood Typing      
    Anti- A Sera  Anti-B Sera Anti- Rh Sera blood type?  
  Person W          
  Person X          
  Person Y          
  Person Z          
  Bindle #___          
  Crime Scene          
             
Conclusion Questions: You must answer in complete sentences in your notebook!  
             
1.  Using your results, what is  the identity  of the individual whose blood was found at 
  the crime scene? Which W, X, Y or Z? Explain.    
2. What percentage to the general population could have the same blood type  
  as your suspect?        
3. Describe how to conclusively determine the identity of the suspect whose blood   
  was left at  crime scene.