1. STEM Whodunit? Practice Lab
Blood Typing Lab
STEM Whodunit?
Practice Lab

2. Blood Typing What’s your blood type? ex., mine is O+
ABO and Rh factors are totally independent of each other

3. ABO Antigens and Antibodies
Surface
Antigens
Antibodies A
Anti-B B
Anti-A AB
A, B
none O

4. The Rh Factor Also called D antigen
Either Rh positive (Rh+) or Rh negative (Rh-)
Surface
Antigens
Rh+
Rh factor
Rh-
none

5. Blood Type Test
Determines blood type and compatibility
Figure 19–7

6. Blood Types
Genetically determined cell surface markers (antigens) on RBCs, including
ABO group – glycolipids on RBC surface
Rh factor – membrane protein

7. 4 Basic Blood Types A has surface antigen A B has surface antigen B
AB has both antigens A and B
O has neither A nor B
A has type B antibodies
B has type A antibodies
O has both A and B antibodies
AB has neither A nor B antibodies

8. 4 Basic Blood Types Antigens also called agglutinogens
Antibodies called agglutinins
Figure 19–6a

9. Blood type questions
Which blood type is the best in emergency settings (hint: which type can be given to anyone?)
Which blood type is the lucky one that can receive blood from any donor?

10. Cross-Reaction If donor and recipient blood types not compatible:
Plasma antibody meets its specific surface antigen and blood will agglutinate (clot) and hemolyze (kill each other)
This is really bad….

11. Cross-Reaction
Figure 19–6b

12. Blood typing procedures
6 trays with three wells each
Victim
Crime scene
Suspect 1 A B Rh A B Rh A B Rh
Suspect 2
Suspect 3
Suspect 4 A B Rh A B Rh A B Rh
6 Bottles of “blood” Bottles of antibodies

13. Blood Typing Procedures
For each well Place 1-2 drops of blood from one bottle in all 3 wells
1-2 drops of crime scene in each of the three wells
1-2 drops of victim in each of the three wells
1-2 drops of suspect 1 in each of the three wells
1-2 drops of suspect 2 in each of the three wells
1-2 drops of suspect 3 in each of the three wells
1-2 drops of suspect 4 in in each of the three wells
For each tray add:
1-3 drops of anti-A serum to one well and stir
1-3 drops of anti-B serum to one well and stir
1-3 drops of anti-Rh serum to one well and stir
Look for clumping reaction

14. Blood type? What is the blood type? x = clumping rxn.
Next question: what antibodies does this person have in their blood? A B Rh X X

15. Example of Determining Genotype – Punnett Square
Mom’s phenotype is group A, genotype AO
Dad’s phenotype is group B, genotype BO B O A
AB 25%
AO 25% (Group A)
BO 25% (Group B)
OO 25% (Group O)

16. Group O Approximately 45% of the population is group O.
No A or B antigens present, think of as “0” antigens present.
These individuals form potent anti-A and anti-B antibodies which circulate in the blood plasma at all times.

17. Group A Approximately 40% of the population is group A.
No B antigens present.
These individuals form potent anti-B antibodies which circulate in the blood plasma at all times.

18. Group B Approximately 11% of the population is group B.
No A antigens present.
These individuals form potent anti-A antibodies which circulate in the blood plasma at all times.

19. Group AB Approximately 4% of the population is group AB.
Both A and B antigens present.
These individuals possess no ABO antibodies.
NOTE: This slide is in error as it only illustrates presence of one antigen not 2.