Lab: Who’s Da Baby Daddy Part 1

Biology / Mrs. O’Connor

Purposes and Objectives

The purposes and objectives of this activity are to:

  • Provide a hands-on opportunity to learn more about genotypes, phenotypes, dominant traits, recessive traits, and codominance.
  • Use Punnet square analysis to solve problems.
  • Connect the process of meiosis with inheritance of traits.
  • Learn more about blood types.

The Dilemma

Ms. Brown is a rather confused young lady. She falls in love with every man that she meets but unfortunately, they do not feel the same way about her. About a year ago, she “fell in love” with three men right around the same time – Mr. Green, Mr. Smith, and Mr. Jones. Soon after, she became pregnant.

Sadly, Ms. Brown is a single mom and she not only needs financial support to raise her child, but she feels that her son needs a father. None of the me have stepped up to claim Baby Bubba as their son. So the big question on Ms. Brown’s mind is, “Who’s the baby’s daddy?” Luckily, each man has agreed to provide a blood sample. With any luck, we can figure out which man is the father.

Use this information to help you complete your data table.

Blood Type / Antigens on Surface / Clumping (agglutination) occurs when exposed to:
A / A / Anti-serum A
B / B / Anti-serum B
AB / A and B / Anti-serum A and B
O / None / Neither anti-serum causes clumping
Rh + / + / Anti-serum Rh
Rh - / None / Anti-serum Rh does not cause clumping

Pre-lab

Before you can participate in this lab activity, you must complete the pre-lab questions below. Read the lab procedure and write the answers in complete sentences on your paper.

  1. How many drops of blood are placed in each well?
  2. How many drops of the anti-serum are placed in each well?
  3. Why do you have 12 toothpicks?
  4. How do you know that you have a positive agglutination reaction?
  5. What will you do with the slides and toothpicks when you are finished with the procedure?
  6. Copy the data table below onto your paper.

Anti-serum A / Anti-serum B / Anti-serum Rh / Blood Type
Mr. Smith
Mr. Jones
Mr. Green
Ms. Brown
Bubba

GET A STAMP

Procedure

  1. Place each slide in a square on the piece of paper provided to you.
  1. Place three to four drops of Mr. Smith’s blood in each well on slide 1.
  1. Place three to four drops of Mr. Jones’s blood in each well on slide 2.
  1. Place three to four drops of Mr. Green’s blood in each well on slide 3.

5. Place three to four drops of Ms. Brown’s blood in each well on slide 4.

  1. Place three to four drops of the Anti-A serum in each A well on the four slides.
  1. Place three to four drops of the Anti-B serum in each B well on the four slides.
  1. Place three to four drops of the Anti-Rh serum in each Rh well on the four slides.
  1. Obtain three toothpicks for EACH blood-typing slides. Stir each well with a separate, clean toothpick for approximately 30 seconds.
  1. Observe each slide and record your observations in your data table. To confirm a positive agglutination reaction, look for clumping. If you can’t tell, try placing the instructions underneath the slide. If you can’t read the text, you have a positive reaction.
  1. When you are finished, dump the blood samples in the sink and rinse out your tray.
  1. Throw the used toothpicks in the trashcan.
  1. Wipe down your lab station.
  1. Write the words “clean up” on your paper. Call Mrs. O over for a stamp.
  1. DO NOT LEAVE YOUR LAB STATION UNTIL YOU HAVE OBTAINED STAMPS FOR CLEANING UP YOUR LAB AREA AND DATA TABLE.
  1. Return to your desk to work on the analysis and conclusions.

Analysis and Conclusions

Answer the questions in complete sentences. Use your notes and the information in your data table to help you.

  1. We watched a segment of the Maury Povich Show prior to the lab.
  2. How did this relate to what we are studying?
  3. How do you feel about people going on talk shows to address problems like this?
  1. You have probably heard the phrase, “It takes two to tango.” Ms. Brown and the men she had relationships with were all promiscuous and this resulted in the birth of a child.
  2. If you were in Ms. Brown’s shoes, would you insist on finding out who fathered your child even though you have no relationship with that person? Why or why not?
  3. If you were one of the men who “messed around” with Ms. Brown, would you be willing to provide a blood sample to determine if you fathered the child? Why or why not?
  1. Now it’s time to work out a few mononhybrid crosses so that we can figure out who fathered Bubba.
  2. Let’s assume that the person with Type A blood has a genotype of AO.
  3. Let’s assume that the person with Type B blood has a blood type of BO.
  4. Let’s also assume that if someone is Rh positive or negative, the individual is homozygous for that trait.
  5. Ms. Brown x Mr. Smith. Describe the possible phenotypes and the probability of those phenotype(s) occurring.
  6. Ms. Brown x Mr. Jones. Describe the possible phenotypes and the probability of those phenotype(s) occurring.
  7. Ms. Brown x Mr. Green. Describe the possible phenotypes and the probability of those phenotype(s) occurring.
  1. Based upon your results, can you conclude who fathered Bubba? Why or why not?
  1. If the testing for blood type does not give us conclusive results, what should be our next step? Justify your answer.
  1. When it comes to donating blood, the blood banks are always seeking people to donate Type O blood. Why is Type O in such demand?
  1. What is the importance of knowing your own blood type?