Genetics Practice Problems
USE THE 5 PT PLAN… SHOW ALL WORK!
1. Bunnies can have straight ears or floppy ears. Straight ears are dominant and floppy ears
are recessive. Using the letter “e” to represent ears, what is each genotype?
_____ = Straight
homozygous dominant
______ = Straight
heterozygous dominant
________ = Floppy
homozygous recessive
2. If a purebred straight eared bunny is crossed with a floppy eared bunny, what percentage of
the offspring will have straight ears?
3. If two bunnies are both heterozygous and are mated, what percentage of the offspring will
have floppy ears? Straight ears?
4. If a heterozygous bunny is crossed with a floppy eared bunny, what are the genotypes and
phenotypes of the offspring?
Genetics Practice Problems
1. For each genotype below, indicate whether it is heterozygous (He) or homozygous (Ho)
AA _____
Bb _____
Cc _____
Dd _____
Ee _____
ff _____
GG _____
HH _____
Ii _____
Jj _____
kk ____
Ll ____
Mm _____
nn _____
OO _____
Pp _____
2. For each of the genotypes below determine what phenotypes would be possible.
Purple flowers are dominant to white
PP _____________
Pp _____________
pp ______________
Brown eyes are dominant to blue
BB ______________
Bb ______________
bb _______________
Round seeds are dominant to wrinkled
RR ___________
Rr ____________
rr _____________
Bobtails are recessive to Long tails
TT ____________
Tt ____________
tt _____________
3. For each phenotype below, list the genotypes (remember to use the letter of the dominant trait)
Straight hair (H) is dominant to curly (h)
Pink flowers (F) are dominant to yellow flowers (f)
_____ straight
____ pink
_____ straight
____ pink
_____ curly
____ yellow
4. Set up the Punnet squares for each of the crosses listed below.
The trait being studied is Round seeds, where round is dominant to wrinkled.
Rr x rr
What percentage of
the offspring will be
round? _________
Rr x Rr
What percentage of
the offspring will be
round? _______
RR x Rr
What percentage of
the offspring will be
round? _______