Download Introduction to Blood Typing

Introduction to Blood Typing
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Read: The Forensics of Blood article,
“Whose Blood is it?” page 2
◦ Answer questions on page 3 of “Do Now”
packet! Questions from Friday 3/2/2012
#’s 1-6 only
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A
B
AB
O
Defined based on which proteins are present on
the surface of RBCs.
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Type A: contain A antigens on RBCs.
Type B: contain B antigens on RBCs.
What makes a person type AB?
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Type AB: Both A & B antigens on RBCs
What makes a person type 0?
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Type O: no antigens on RBCs
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Add proteins called antibodies to a blood
sample.
What 2 antibodies do forensic scientists
use to determine blood type? What are
antibodies supposed to do?
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Anti A and Anti-B antibodies, which bind to A
& B antigens respectively
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Antibodies can be used instantly to determine
blood type of blood present at a crime scene
and from potential suspects.
What must be done with the blood to
confirm whether a suspect is the actual
criminal?
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DNA tests!
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Karl Landsteiner discovered that there are
four different types of human blood based on
the presence of specific antigens found on
the surface of red blood cells.
1940: Landsteiner and Weiner reported the
discovery of Rh factor by studying the blood
of the Rhesus monkey.
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Antigens:
◦ Substances that trigger an immune response
◦ Can stimulate the body to make antibodies
◦ Certain antigens (proteins) found on a RBCs
membrane account for blood type.
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Antibody: a substance that reacts with an
antigen
will recognize and attack foreign molecules
that may enter from the outside world.
A person's plasma does not contain any
antibodies that will bind to molecules that are
part of his or her own body
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Human Blood Types: 2:54
◦ http://www.youtube.com/watch?v=wN--_z9eyJU
◦ http://www.redcrossblood.org/learn-aboutblood/blood-types
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O: Universal Donors:
◦ There are NO molecules on the surface to trigger an
immune response
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AB: Universal Recipients:
◦ Do not have antibodies that will recognize type A/B
surface molecules.
ABO blood system:
O can only receive blood from: O
A can receive blood from: A and O
B can receive blood from: B and O
AB can receive blood from: AB, A, B and O
Rh blood system
Rh+ can receive blood from: Rh+ and RhRh- can receive blood from: Rh-
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Take out “Blood Basics” sheet
Today:
◦ Quick review
◦ Finish blood typing ppt
◦ Testing tutorial simulation
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Rhesus factor: certain blood protein
discovered while studying Rhesus monkeys.
The presence of the protein, or lack of it, is
known as the Rh factor.
Rh+: has the
protein
Rh-: does not
have the
protein
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http://www.nobelprize.org/educational/medi
cine/bloodtypinggame/2.html
http://www.nobelprize.org/educational/medi
cine/bloodtypinggame/index.html
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Investigators will use anti-A and anti-B
serums to see which causes clumping
Blood Type
Anti-Serum
Results
A
A
Clumps
B
B
Clumps
AB
A or B
Clumps
O
A or B
No Clumps