Name
Monsters Inc. Genetics
1. Which of Mike’s traits are heterozygous?
2. Which of Mike’s traits are homozygous dominant?
3. Which of Mike’s traits are homozygous recessive?
4. Which of Sulley’s traits are heterozygous?
5. Which of Sulley’s traits are homozygous dominant?
6. Which of Sulley’s traits are homozygous recessive?
Genotype
Phenotype
Yy
Yellow body color
ee
One eye
CC
Clawed toes
Ff
Four fingers
Genotype
Phenotype
GG
Green body color
Pp
Purple spots
Hh
Horned ears
bb
Blue eyes
Here is the information for members of Mike’s species:

Yellow body color [Y] is dominant to orange body color [y]

Two eyes [E] are dominant to one eye [e]

Claws on toes [C] are dominant to no claws [c]

Four fingers [F] are dominant to three fingers [f]
7. Color the monsters according to the following genotypes
8. Mike’s father has the genotype: Yy : Ee : Cc: Ff
Mike’s mother has the genotype: yy : Ee : Cc: ff
Mike’s Father
Mike’s Mother
Here is the information for members of Sulley’s species:

Green body color [G] is dominant to blue body color [g]

Purple spots [P] are dominant to black spots [p]

Horned ears [H] are dominant to no horns [h]

Brown eyes [B] are dominant to blue eyes [b]
9. For each phenotype of monsters in Sulley’s species, list the possible genotype(s):
Phenotype
Green body color
Blue body color
Purple spots
Black spots
Genotype(s)
Phenotype
Horned ears
No horns
Brown eyes
Blue eyes
Genotype(s)
10. Sulley’s genotype is GG and his phenotype is green. Can either of his parents be blue?
Explain why or why not:
11. Sulley has the genotype Pp and his phenotype is purple spots. His father is PP and has purple
spots. What two possible genotypes and phenotypes does his mother have?
Possibility 1: Genotype
Phenotype
Possibility 2: Genotype
Phenotype
12. Sulley has the genotype Hh and his phenotype is horns. His mother does not have horns. Does his
father have horns? Explain how you know:
13. Sulley has the genotype bb and his phenotype is blue eyes. Both of his parents have brown eyes.
How can two brown eyed parents have a blue eyed child? Use possible phenotypes to explain how
this can happen.