Blood Type Genetics - Science with Ms. Fonda

1 Name: _____ Band: _____ Date: _____ bikini bottom : Blood Type Genetics and Codominance The Problem: Two starfish couples had babies in the same hospital at the same time. Patrick and Patti had twins: a boy named Paul and a girl named Patricia. Lawrence and Lisa had a girl, Lucy. After seeing all of the babies, Lisa insisted that the hospital had switched the baby girls, giving Lisa s real daughter to Patti. The hospital decided to perform Blood type tests for both families to see if Lisa was right. The Information: There are many different ways to classify Blood types , but the most common Blood type classification system is the ABO (said A-B-O ) system. There are four Blood types in the ABO system: Type A, Type B, Type AB, and Type O.

2 These Blood types refer to different versions of carbohydrates (complex sugar molecules) that stick out of the surface of red Blood cells. 1. How are Type A carbohydrates depicted in the diagram above? 2. How are Type B carbohydrates depicted in the diagram above? Those Type A and Type B carbohydrate molecules are called antigens. Antigens are also present on the surface of viruses and bacteria things that invade your body and do harm. So how does your body tell the difference between your own cells and an intruder? It looks at the antigens: if the antigens on the foreign substance don t match the ones on the rest of your cells, your body produces special proteins called antibodies to kill the intruder.

3 3. Your Blood cells have Type A antigens. Will your body produce antibodies to kill a virus with Type B antigens? 4. You have Blood type AB. Will your body produce antibodies to kill a virus with Type A antigens? 5. Your body will also attack Blood cells that have the wrong antibodies. Test your understanding of Blood groups by filling in the blanks in the chart below. If a person loses a lot of Blood , he/she is given a Blood transfusion: someone else s Blood is injected into the person s Blood vessels. If you are given Blood that does not match your Blood type, the antibodies in your Blood will attack the antigens on the donated Blood , causing the donated red Blood cells to burst or clump together and block Blood vessels.

4 Transfusion reactions can be fatal, so doctors always test a person s Blood type before giving him/her donated Blood . 6. Test your understanding of Blood groups by completing the table below. Blood Group Antigens on red Blood cells Antibodies in Blood Can receive Blood from Can give Blood to A A Anti-B A and O A and AB B B AB A and B O None 7. Based on the table above, which Blood type would be considered a universal donor (someone who can give Blood to anyone)? Your Blood type is established before you are born by your genes, which were inherited from your parents. You receive one allele for Blood type from your mom and one allele for Blood type from your dad. The three possible alleles are: IA: codes for A antigens on red Blood cells IB: codes for B antigens on red Blood cells i: does not code for any antigens Everyone has TWO alleles for Blood type in their cells, which means there are six possible genotypes and four possible Blood types .

5 8. List the six possible genotypes (combinations of alleles) for Blood type. Group them according to the four possible phenotypes ( Blood type). Phenotype Genotype Type A (two genotypes possible) Type B (two genotypes possible) Type AB (one genotype possible) Type O (one genotype possible) 9. In a heterozygous IAi person, which allele is dominant, IA or i? Explain your reasoning, but do not use capitalization of allele letter as a reason! Codominance is when two alleles of a gene both influence the phenotype of an individual. Neither allele is recessive; both alleles are dominant. 10. Which one of the genotypes you listed in question 8 results in a phenotype that provides evidence of codominance?

6 Hint: look back at the diagrams of the antigens. 11. Draw a picture of a red Blood cell for the genotype you identified in question 10 to illustrate how both alleles influence Blood type in this case. 12. Each biological parent gives one of their two Blood type alleles to their child. For example, a father who has Blood type AB has the genotype _____, so he will produce sperm with either an IA or an IB allele; he can give either an IA or an IB allele to his child. If the mother has Blood type O, her genotype must be _____, and she can only give an _____ allele to her child. 13. Complete the Punnett square shown below for the parents mentioned in question 12. a. What is the percent chance of having a child with type A Blood ?

7 _____ b. What is the percent chance of having a child with type B Blood ? _____ c. What is the percent chace of having a child with type AB Blood ? _____ d. What is the percent chance of having a child with type O Blood ? _____ 14. Create a Punnett square for a mother who has type A Blood and a father who has type B Blood . Determine the percent chance of these parents having a child with type O Blood . Solve the Problem: Lisa has type B Blood . Lawrence has type A Blood . Lucy has type O Blood . Patrick has type AB Blood . Patti has type B Blood . Patricia has type A Blood . Paul has type B Blood . 15. Is it possible for Patrick and Patti to have a child with type O Blood ? Use a Punnett square to support your answer.

8 16. Did Lisa receive her own baby at the hospital, or did she receive Patrick s and Patti s baby girl? How do you know? bikini bottom Genetics : Incomplete Dominance SpongeBob is growing flowers for his pal Sandy. Her favorite flowers, Poofkins, are found in red, blue, and purple varieties. The red Poofkins are purebred RR, and the blue Poofkins are purebred rr. Purple Poofkins result from the heterozygous genotype. Purple Poofkins are an example of incomplete dominance: the dominant allele and the recessive both affect the phenotype, and what you see is a blend of both alleles. 1. Write the correct genotype for each color of Poofkin: a. Red: _____ b. Blue: _____ c. Purple: _____ 2.

9 What would happen if SpongeBob crossed a red Poofkin with a blue Poofkin? Create a Punnett square to determine the percent chance of producing red, blue, and purple flowers. 3. What would happen if SpongeBob crossed two purple Poofkins? Create a Punnett square to determine the percent chance of producing red, blue, and purple flowers. 4. What would happen if SpongeBob crossed a purple Poofkin with a blue Poofkin? Create a Punnett square to determine the percent chance of producing red, blue, and purple flowers. SpongeBob and Patrick love to go jellyfishing at Jellyfish Fields. The fields are home to a special type of green jellyfish, and only really great jellyfishermen are lucky enough to catch some on every trip because many of the jellyfish are yellow, QQ, or blue, qq.

10 The jellyfish that are green have that color as a result of incomplete dominance. 5. What would happen if SpongeBob and Patrick crossed two green jellyfish? Create a Punnett square to determine the percent chance of producing yellow, blue, and green jellyfish. 6. What would happen if they crossed a yellow jellyfish with a green jellyfish? Create a Punnett square to determine the percent chance of producing yellow, blue, and green jellyfish. 7. What would happen if they crossed a blue jellyfish with a yellow jellyfish? Create a Punnett square to determine the percent chance of producing yellow, blue, and green jellyfish. 8. What would happen if they crossed a blue jellyfish with a green jellyfish? Create a Punnett square to determine the percent chance of producing yellow, blue, and green jellyfish.