Polygenics Lab II Answer Key

“Polygenics Lab” Experimental Questions: Why do some traits appear in nearly endless varieties? Introduction: Polygenic traits are traits that are controlled by more than one gene, i.e. height, weight, hair color, skin color. If these traits were controlled by Mendelian Inheritance humans would only show two heights, a tall height or a short height. Polygenic inheritance allows a wide range or spectrum of traits. Polygenic Gamete (Sex Cell) Formation: A man is 5 feet 7 inches tall, has 3 heads (tall genes) and 3 tails (short genes). He will give 3 genes to his child. These 3 genes can be given randomly. He can give 3 tall genes and no short genes, 2 tall genes and 1 short, 1 tall gene and 2 short, 0 tall genes and 3 short. These are all the possible combinations that he can give his child. The height of the mother will dictate the genes that she will give to the child. The combination of the mother's genes and the father's genes will decide the height of the child. 1) of their genetic material does each parent give to their child? Explain why. PreWhat Labfraction Questions: 2) If a male is 5 feet 9 inches tall, it means that he has 4 tall genes and 2 short. He will only give 3 genes to his child. What are the possible combinations of genes that he can give? He can give _____ tall and ______ short He can give _____ tall and ______ short He can give _____ tall and ______ short 3) The male is 5 feet 7 inches and the female is 5 feet 5 inches. Is it possible for them to give their child the necessary genes so the child can be 5 feet 11 inches tall? Explain your answer. Procedure: 1. Assuming both parents carry three tall genes and three short genes, you will model the inheritance of height for ten different offspring. Flip a coin six times to determine how many tall and short genes the child inherits. Heads represents a tall gene and tails represents a short gene. 2. Record all of your data along with the class data in the tables below Data: Table 1: Group results Flip (Your Group) Number of tails Number of heads 1 2 3 4 5 Table 1: continued Flip (Your Group) 6 7 8 9 10 Number of tails Number of heads Table 2: Group and class results Flip Situation 0T6H 1T 5H 2T 4H 3T 3H 4T 2H 5T 1H 6T 0H Your Group Total Class Total Construct a Bar Graph for both your results and the class results. Conclusion: Use the following Height Table to answer the questions. Penny Situation Height O Tails and 6 Heads 6 feet 1 inch 1 Tail and 5 Heads 5 feet 11 inches 2 Tails and 4 Heads 5 feet 9 inches 3 Tails and 3 Heads 5 feet 7 inches 4 Tails and 2 Heads 5 feet 5 inches 5 Tails and 1 Head 5 feet 3 inches 6 Tails and 0 Heads 5 feet 1 inch Remember: Heads are tall genes. Tails are short genes. Conclusions: 1) If the male is 5 feet 5 inches tall and the female is 5 feet 3 inches tall, what is the tallest height that their child could attain? Explain. 2) If the male is 5 feet 7 inches tall and the mother is 5 feet 3 inches tall, what is the shortest height their child could attain? Explain. 3) List 3 other polygenic traits. 4) How are polygenic traits different from traits that only require 2 genes? 5) Why do you think that some children are taller than their parents? 6) Analyze the class data and propose an explanation for an apparent trends in height. Answer Key! 1) Do parents give (All or Half) of their genetic material to their children? Half 2) If a male is 5 feet 9 inches tall, it means that he has 4 tall genes and 2 short. He will only give 3 genes to his child. What are the possible combinations of genes that he can give? He can give ___3__ tall and __0____ short He can give ___2__ tall and __1____ short He can give ___1__ tall and __2____ short 3) The male is 5 feet 7 inches and the female is 5 feet 5 inches. Is it possible for them to give their child the necessary genes so the child can be 5 feet 11 inches tall? Explain your answer. Diagrams are often useful. The father can give 3 talls and 0 shorts and the mother can give 2 talls and 1 short. The child will be 5 feet 11 inches tall. 4) If 2 parents are 5 feet 7 inches, is it possible to have a child that is 6 feet tall? Explain how this is possible. Yes. Both parents can give 3 talls and 0 shorts. This will give the child 6 talls and 0 shorts. This means the child will be 6 feet 1 inch tall. 5) If the male is 5 feet 5 inches tall and the female is 5 feet 3 inches tall, what is the tallest height that their child could attain? Explain. The male can give 2 talls and 1 short and the female can give 1 tall and 2 shorts. The child could have 3 tall and 3 short, making the child 5 feet 7 inches tall. 6) If the male is 5 feet 7 inches tall and the mother is 5 feet 3 inches tall, what is the shortest height their child could attain? Explain. The male and female can give 3 short and 0 talls. The child could have 6 shorts. This will make the child 5 feet one inch tall. 7) List 3 other polygenic traits. Hair color, skin color, eye color, body shape—anything that deals with size, shape, color or number (like fingerprints—the total ridge count). 8) How are polygenic traits different from traits that only require 2 genes? The polygenic traits have a wide variation in each trait. 9) Why do you think that some children are taller than their parents? The children can have more tall genes than either parent. The environment also plays a role in the expression of traits. Remember Genotype + Environment = Phenotype.