Name __________________________
Period________Date______________
Lab: Are You My Type?
Purpose: To simulate the process involved in determining human blood types.
Background:
Karl Landsteiner discovered the ABO blood groups in the early 1900’s. This
important discovery made blood transfusions safe. In transfusions, the blood types of the donor and
the recipient must be carefully matched. Transfusion of the wrong type of blood can result in
agglutination, or clumping of red blood cells. Agglutination is the result of an immune reaction
between antigens on the red blood cells of the donor and the antibodies in the blood plasma of the
recipient.
Materials:
o
o
o
o
o
o
4 clear depression well plates
glass-marking pencil
toothpicks
bottle of “anti-A serum” (blue)
bottle of “anti-B serum” (yellow)
4 simulated blood samples: Mr Smith, Mr Jones, Mr Brown, Mr Green
Safety:1. Keep all opened bottles from touching any other solutions.
2. Wash your hands after touching the chemicals.
3. Wear safety goggles at all times!
Procedure:
1. Review Table 1.
Table 1: Safe Blood Transfusions
Blood Type
Antigen on Red Blood
Cells
Antibody in Plasma
(fluid portion of blood)
Blood Types That Can Be Received
Safely in Transfusions
A
A
anti-B
A and O
B
B
anti-A
B and O
AB
A and B
none
A, B, AB, and O
O
none
anti-A and anti-B
O
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2. Observe the demo, listen to your teacher’s explanation, and refer to the chart/poster on agglutination
(clumping) of blood. Fill in Table 2 below using the information learned.
Table 2: Expected Blood Typing Results
Results
Blood Type
(A, B, AB, or O)
agglutination with anti-A serum only
agglutination with anti-B serum only
agglutination with anti-A and anti-B serums
no agglutination with either serum
3. Using the glass-marking pencil or marker, mark one depression slide with “S” for
Mr Smith.
4. On the slide labeled “S”, place 2 drops of “anti-A serum” (blue) in the well that is
labeled “A”.
5. On the same slide, place 2 drops of “anti-B serum” (yellow) in the well that is labeled “B”.
6. Without touching the dropper bottle to the “serum”, add 2 drops of Mr.
Smith’s simulated blood to well “A” .
7. Add 2 drops of Mr. Smith’s blood to well “B”.
8.
Using different toothpicks, stir the solutions in each well.
9. Look for precipitation (the formation of a gel-like substance) in the mixtures
on the slide. Precipitation simulates the agglutination (clumping) of blood.
10. Fill in Table 3, marking “yes” or “no” for precipitation. Based on the precipitation results and Table
2’s expected results, determine Mr. Smith’s blood type. Record it in Table 3 on the following page.
11. Repeat steps 4-10 for the other simulated blood samples (Mr. Jones, Mr. Brown, and Mr. Green).
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Table 3: Results of Blood Typing
Sample
#
Patient’s Name
1
Mr. Smith
2
Mr. Jones
3
Ms. Brown
4
Mr. Green
Precipitation with
“anti-A”?
(yes or no)
Precipitation with
“anti-B”?
(yes or no)
Simulated
Blood Type
(A, B, AB. or O)
Carefully wash and dry the slides and toothpicks. Be sure all bottles are closed tightly.
Analysis:
1. Why does type A blood agglutinate (clump) when it is added to anti-A serum?
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2. Why was there no agglutination when type O blood was added to anti-A and anti-B serums?
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3. Why should a person with type O blood never be given a transfusion of any other type of blood except
type O?
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4. Why can a person with type AB blood be safely given all four main blood types?
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