Polygenic Traits with Pennies Lab
Name ________________________
Introduction: In this activity you will model the inheritance of a trait that is controlled by more than
one gene.
Materials: 6 pennies, graph paper or create a graph website:
https://nces.ed.gov/nceskids/createagraph/
Procedure:
1. You will carefully flip each of the 6 coins and place them on the lab table.
2. Record the number of heads and tails in Table 1.
3. Repeat steps 1 and 2 until Table 1 is complete.
4. Complete Table 2 by adding up the number of times each of the following situations occurred.
a.
0 tails and 6 heads
b. 1 tail and 5 heads
c. 2 tails and 4 heads
d. 3 tails and 3 heads
e. 4 tails and 2 heads
f. 5 tails and 1 head
g. 6 tails and 0 heads
Record your results for Table 2 in the “Your Totals” row of the data table.
5. Record the class results in Table 2. (This is done for you)
6. Now complete Table 2 by filling in the Overall Totals. To do this add the totals in each column (Your
Totals + Period 1 Class Totals + Period 2 Class Totals).
7. Construct two bar graph one using your data and one using the Overall Totals. The dependent
variable (y-axis) is the number of times each situation occurred. The independent variable (x-axis) is
the number of tails and heads. Remember to give your graph a title, label your axis, and create a key.
8. Use your data and the information below to answer the analysis questions.
Supplemental Information:
Polygenic traits are traits that are controlled by more than one gene i.e. height, hair color, eye color,
skin color. This allows for a wide range of phenotypes. For example, if height was controlled by one
gene (A) and if AA = 6 feet, Aa = 5 feet 7 inches, aa = 5 feet THEN all people would be one of these 3
different heights. Instead, there is a very wide range of human heights.
Results:
Table 1: Your Results
Flip
# tails
# heads
1
2
3
4
5
Flip
# tails
# heads
6
7
8
9
10
Table 2: Class results
Flip results
0T 6H
1T 5H
2T 4H
3T 3H
4T 2H
5T 1H
6T 0H
6
18
70
73
43
18
4
7
14
33
44
34
13
5
Your Totals
Period 1
Class Total
Period 2
Class Total
Overall
Total
Analysis: Use the following Human Height Data Table to help you answer the questions.
***REMEMBER: Heads are dominant and Tails are recessive!!
Penny Situation
O tails and 6 heads
1 tail and 5 heads
2 tails and 4 heads
3 tails and 3 heads
4 tails and 2 heads
5 tails and 1 head
6 tails and 0 heads
9.
Height
6’ 1”
5’ 11”
5’ 9”
5’ 7”
5’ 5”
5’ 3”
5’ 1”
How much of their genetic material do parents pass on to their children? ________________
EXAMPLE: A man is 5’7” tall. His genotype consists of 3 dominant alleles (heads) and 3 recessive
alleles (tails). He will pass on a random assortment of 3 of these alleles to his child.
a.
he can pass on 3 dominant alleles and no recessive alleles.
b. he can pass on 2 dominant alleles and 1 recessive allele.
c. he can pass on 1 dominant allele and 2 recessive alleles.
d. he can pass on 0 dominant alleles and 3 recessive alleles.
These are all the possible combinations that he can pass on to his child. The height of the mother will
determine which alleles she can pass on to the child. The combination of the mothers alleles and the
fathers alleles will determine the height of the child.
10. If a male is 5’ 9” tall, it means that he has 4 dominant alleles and 2 recessive alleles. He will pass on
only 3 alleles to his child. What are the possible combinations that he could give?
a.
he can pass on _____dominant and ____recessive.
b. he can pass on _____ dominant and ____ recessive.
c. he can pass on _____ dominant and ____ recessive.
11. A male is 5’ 7” and a female is 5’ 5”. Is it possible for them to give their child the alleles necessary
so that the child can be 5’ 11” tall? Explain your answer including diagrams.
12. If 2 parents are 5’ 7” tall, is it possible to have a child that is 6’ tall? Explain how this would be
possible.
13. If a male is 5’ 5” tall and a female is 5’ 3” tall, what is the tallest height that their child could
attain? Explain your answer.
14. If a male is 5’ 7” tall and a female is 5’ 3” tall, what is the shortest height that their child could
attain? Explain your answer.
15. Use your textbook or the internet to find at least 3 other traits that are polygenic.
16. Describe how the inheritance of polygenic traits is different than the inheritance of a trait
controlled by a single gene.
17. Explain why some children are bigger than their parents? Are there any factors other than genetics
that might contribute as well?