Name ___________________________
Date __________
FA#5: Gummy Bear Cross-breeding Inquiry Lab
Key vocabulary: alleles, phenotype, genotype
Role: Gummy bear breeder for a local zoo
Part I task: To find out the answer to this question- How can the offspring’s physical traits (phenotypes)
be used to determine the possible genetic make-up (genotypes) of the parents?
Hypothesis:
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Materials: 1 bag of F1 generation gummy bears from the cross-breeding experiment
Procedure:
1) Obtain a bag of bears. Pour them out onto the table and count them. How many do you have? _______
2) Sort the bears according to an observable physical trait (phenotype). Which trait will you use to sort
the bears? ______________________
3) Fill in the 1st three columns of the data table below for your generation of gummy bears. Note:
depending on your cross number, all of the rows may not be filled in.
Possible
Cross #
Phenotype(s)
# of gummy
Possible genotype(s)
phenotypes &
bears with that
of your gummy
genotypes of the
phenotype
bears
parents
Phenotype:
Total # of bears
Genotype:
4) As a class we will select letter symbols to represent the alleles for each phenotype.
5) Predict the genotypes or allele combinations for each of your gummy bears that are different. Recall
that organisms get ½ of their genetic information from each parent; so 1 allele from each parent.
6) Record the possible genotypes in the 4th column in the data table above using the letters that we
decided upon in step #4.
7) Hypothesize the probable phenotypes and genotypes of the original parental cross that produced your
types of gummy bears.
8) Record them in column 5 of the data table.
Conclusion: How can the offspring’s phenotypes be used to determine the possible genotypes of the
parents?
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Going further
Predict how coat color is inherited in common animals. Be specific by using alleles to help make your
prediction.
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Adapted from “Gummy Bear Genetics” by William P. Parker and Cynthia L. Thomas, 1998