Name:
Date:
Per:
Blood Typing Lab
Introduction: Kanye West has been shot! His wife, Kim
Kardashian, has been listed as the top suspect. She was
found at a mall nearby their Calabasas home with a
suspicious blood stain on her Louis Vuitton shoe. As a
forensic scientist, your job is to compare the blood sample
from Kim Kardashian’s shoe to known blood types. If the
sample matches Kanye’s blood type, B positive, then Kim
could be the culprit! If the stain does not match Kanye’s
blood type, she will be deemed innocent.
BACKGROUND KNOWLEDGE: How Blood Typing Works
Around 1900, it was discovered that there are at least 4 different kinds of human blood.
This is based on the fact that there may be one or more proteins called antigens on the
surface of the red blood cells. These antigens are defined as A and B.
People also produce antibodies to fight against the antigens that are not present in their
own red blood cells. The body sees foreign antigens as dangerous particles that must be
attacked! Antibodies bind to specific antigens via Van der Waal forces. Once the
antibodies and antigens bond to each other, the foreign antigen is destroyed. A person
with antigen A on his red blood cells will produce anti-B antibodies; a person with antigen
B will produce anti-A antibodies; a person with neither A nor B antigens will produce both
anti-A and anti-B antibodies; and, a person with both antigens A and B will not produce
these antibodies.
The 4 blood types are known as A, B, AB and O. Blood type O (persons with neither A nor
B antigens) is the most common in the United States (45% of the population). Type A is
found in 39% of the population. Type B is found in 12% of the population, and type AB is
found in only 4% of the population.
Because of the different blood types, certain blood groups can only give or receive blood
from other specific blood groups:
Blood
Type
Antigens on
Blood Cells
Antibodies
in Plasma
Can Give
Blood to
A
A
anti-B
A or AB
O or A
B
B
anti-A
B or AB
O or B
AB
A and B
none
AB
O
none
anti-A &-B
O,A,B,AB
Can Receive
Blood from
O, A, B, AB
O
Name:
Date:
Per:
If blood cells are mixed with antibodies, the cells will clump together. This is called
agglutination. Agglutination can block a person’s arteries and slow down blood flow. This
is why it can be very dangerous if you receive the wrong blood type in a transfusion.
Blood typing is performed by mixing a small sample of blood with anti-A or anti-B
antibodies (called antiserum). The presence or absence of clumping is determined for
each type of antiserum used.
-
If clumping occurs with only anti-A serum, then the blood type is A.
If clumping occurs only with anti-B serum, then the blood type is B.
Clumping with both antiserums indicates that the blood type is AB.
No clumping with either serum indicates that you have blood type O.
Anti-A Serum
Reaction
Anti-B serum
Reaction
Blood Type
of Person
Clumps
No Clumps
Type A
No Clumps
Clumps
Type B
Clumps
Clumps
Type AB
No Clumps
No Clumps
Type O
A person’s blood type is inherited from their parents, just like any other genetic trait.
Persons with blood type A have inherited one or two copies of the gene for the A antigen,
one from each parent. Persons with blood type B have inherited one or two copies of the
gene for the B antigen. Persons with blood type AB have inherited on copy of the A
antigen from one parent and one copy of the B antigen gene from the other parent.
Persons with blood type O inherited neither A nor B genes from their parents.
Blood typing can be used in legal situations involving identification or disputed paternity.
In paternity cases a comparison of the blood types of mother, child, and alleged father
may be used to exclude a man as the possible parent of a child. For example, a child with
the blood type AB whose mother is type A could not have a father whose blood type is A
or O. The father must have blood type B.
NOTE: We are using simulated blood for this activity.
Before we start…ONE QUESTION FOR YOU…
We know what the “anti-A” and “anti-B” serums are used for. What do you think this
means “Anti-Rh” is for? What blood type will it help identify?
PROCEDURE – Determining Blood Type
Control Group – known blood samples (A, B, AB, & O)
Internal Thinking: why are we testing these known blood samples?
For each blood sample:
Name:
Date:
Per:
Step 1: Place 2 drops of blood in each of three wells.
Step 2: Place 2 drops of the anti-A serum on the blood in the A well and use a
clean toothpick to stir the serum for a few seconds
Step 3: Make observations in your table below
Step 4: Place 2 drops of the anti-B serum on the blood in the B well and use a
clean toothpick to stir the serum for a few seconds
Step 5: Make observations in your table below
Step 6: Place 2 drops of the anti-Rh serum on the blood in the B well and use a
clean toothpick to stir the serum for a few seconds
Step 7: Make observations in your table below
Step 8: Repeat for the other blood samples
Experimental Group – unknown blood solution
Internal Thinking: why are we testing this unknown blood sample? What will it tell
us?
Step 1: Add two drops of unknown blood solution into three new wells
Step 2: Repeat the Steps 2-7 above, and record observations in your table below.
P r e - l a b R e q u i r e m e n t s :.
1. APA Title Page
2. Typed introduction paragraph:
 Follow template on project 2 brief (same as murder lab)
 Background information should include research-based facts about:
-chemical bonds -Van der Waal forces (What are they; How are they different
from other types of bonds?) -Why Van der Waal forces are important in the
bond between antibodies and antigens. -how to identify the different blood
types –Why blood typing is important
 Hypothesis: Write as an “If______, then _______” sentence structure. Think
about your prediction. If an antibody interacted with an antigen via Van der
Waal forces, what visible change would occur? What would this mean about a
person’s blood type?
 Sample hypothesis sentence frames: “If the unknown blood sample matches a
known blood type, then it will ____________________________.” “If an
antiserum interacts via Van der Waal forces with an antigen, then
________________ will occur, indicating ____________________.”
3. Methods paragraph (typed)
 Do your best! This is a rough draft that you will be able to edit later. It is
useful to write it ahead of time to get a jump start on the write up, and to
familiarize yourself with the procedure you will be performing.
 Write it by reading the procedures in this lab and summarizing the key points.
 When you edit later, be sure to include the lab equipment that you used (with
size in mL), how many mL of blood you tested, and how many trials you
performed
NAME:________________________________Period: ________
Date: _____________
Blood Typing Lab
DATA AND OBSERVATIONS
Observations with anti- Observations with antiA
B
Control – Type
A
Control – Type
B
Control – Type
AB
Control – Type
O
Unknown Blood
Sample from
Kim’s shoe
Observations with antiRh
NAME:________________________________Period: ________
Date: _____________
Blood Typing Lab
Analysis Questions:
1. What blood type was the sample found on Kim Kardashian’s shoe? How can you tell?
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
2. Kanye’s blood is B+. What antigens does Kanye’s blood have? What antibodies does
Kanye’s blood have? Do these match the antigens and antibodies found on Kim’s shoe?
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
3. Could Kim Kardashian be guilty, based on the blood results? Is the blood test alone
enough to determine whether she is innocent or guilty? Explain.
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________