Investigation: How Can Popsicle Sticks Be Used to Model Heredity?
 Page ID
 21235
In this activity, you will use popsicle sticks to model the process of gamete formation and the combining of sperm and egg to create offspring. Results of the simulation can then be compared to Punnett square expected results.
 The image shows a male and female hornmonster, each with different genetic traits. The allele for one horns is dominant over the allele for two horns. Which hornmonster has the dominant allele?
 Obtain four popsicle sticks that will represent the chromosomes of your parents. Arrange them so that the male’s set (Hh) is on one side and the female’s set (hh) is on the other side. *The M1,M2, F1, F2 labels will help you if you get them confused.
 Flip the sticks over so that you can’t see their labels. Choose one chromosome from the mother pile and another from the father pile. This represents the chromosomes each parent is “donating” to the next generation.
Data
(Repeat the exchange 8 times to produce 8 offspring)
Genotype (letters) 
Phenotype 

Offspring 1 

Offspring 2 

Offspring 3 

Offspring 4 

Offspring 5 

Offspring 6 

Offspring 7 

Offspring 8 
Data Analysis
 How many of out of 8 have one horn? What is the percentage?
 How many of out of 8 have two horns? What is the percentage?
 Show the cross using a Punnett square. Hh x hh
 From the cross above, how many have ONE HORN ______ out of 8
How many have TWO HORNS ______ out of 8  Compare this number to your simulation (where you flipped the sticks). Does the punnett square prediction match the results of your crosses?
 What if the female had the genotype Hh? Show the cross between the new parents Hh x Hh
What percentage has one horn? What percentage has two horns?  Show the cross if the parents are HH x Hh.
What percentage has one horn? What percentage has two horns?