Inheritance and Blood Typing Vanderbilt Student Volunteers for Science Spring, 2006 Training Presentations.

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?– 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• 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)• 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.

– 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 Anti-B 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.