Transcript Genetics and Blood Typing - Awesome Science Teacher Resources

Inheritance and Blood Typing
Vanderbilt Student Volunteers for Science
Spring, 2006
Training Presentations
Important!!!
• Please use this resource to reinforce your
understanding of the lesson! Make sure you
have read and understand the entire lesson prior
to picking up the kit!
• We recommend that you work through the kit
with your team prior to going into the classroom.
• This presentation does not contain the entire
lesson—only selected experiments that may be
difficult to visualize and/or understand.
I. Introduction
• How much blood is in the
human body?
– About 5 liters
• What is in blood?
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Red blood cells (RBC)
White blood cells (WBC)
Plasma
Platelets
• What is blood type?
– A way to characterize what
kind of proteins are present
on someone’s red blood
cells
II. Red Blood Cell Demo (p. 2)
• RBC has proteins on its
surface that determine what
blood type a person is—these
proteins are called antigens.
– Straight pipe cleaner—A
antigen (an A blood cell)
– Forked pipe cleaner—B
antigen (a B blood cell)
– Both pipe cleaners (AB cell)
– No pipe cleaners (O cell)
• If a person’s RBC are lacking a
type of antigen (A or B), then
their blood contains antibodies
to the missing antigen
– The antibodies will attack and
destroy any blood cells with
that antigen that are
transfused or transplanted.
III. Blood Genetics and Punnett
Squares (p. 3)
• Antigens and thus, blood type, are determined by the
genes that get passed on from someone’s parents.
• Explain that each parent (and each person) has two
blood type genes. This is what’s known as a genotype,
or what genes are in someone’s body. Each parent will
pass on one of these genes to their child.
• These genes are for the A antigen or the B antigen. The
combination of two of these genes is what blood type
one will be.
• Punnett squares can be used to help figure out a genetic
trait, like blood type (see figures in lesson).
• Review dominant, recessive and co-dominant
IV. The Kidney Problem
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Read the kidney scenario in the
manual.
Remind the students that the
blood samples are not really
blood.
Students will test the samples for
each person by combining sera
that reacts with A or B antigens on
the surfaces of red blood cells.
A sample is positive for an antigen
by observing whether
agglutination (clumping) occurs.
– If the blood clumps for the anti-A
serum and not the anti-B serum,
then the blood type is A.
– If it clumps for the anti-B and not
for the anti-A, then the blood type
is B.
– If it clumps for both, the blood type
is AB.
– If there is no clumping, then the
blood type is O.
III. The Kidney Problem (p. 5)
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Divide the students into pairs. Pass out safety
goggles, and plastic gloves to each student and
one set of materials to each pair of students.
Orient the students to where the rows (going
across) and the columns (going down) are located.
Have students add 15 drops off the following
samples in the rows indicated.
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Mrs. Sanderson’s samples to the first two wells in row
A
Mr. Sanderson’s samples to the first two wells in row B
Jill’s samples to the first two rows in row C.
Jack’s samples to the first two rows in row D
Have students add 10 drops of anti-A (blue) to each
well in column 1.
Observe whether a precipitate (or cloudiness)
occurs. Record observations on the observation
sheet.
Have students add 10 drops of anti-B (yellow) to
each well in column 2.
Observe whether a precipitate (or cloudiness)
occurs. Record observations on the observation
sheet.
Tell the students to fill in the Anti-A serum and AntiB serum rows in their data tables with “+” or “-”,
depending on whether there was agglutination
(cloudiness or clumping) in a particular well.
V. Analysis (p. 6)
• Ask students what each family member’s
possible genotype is. Write these answers on
the board and/or share with the class.
• The data tables show that Jack does not have a
family member with the same blood type. Since
he is type O, he has antibodies against type A
and type B blood, so none of his family members
can donate to him.
• Let students know that Jack eventually received
his kidney through a special charity event by the
Tennessee Titans that found someone with the
same blood type who was willing to donate part
of a kidney.