ANSWER KEY
Pedigree Problems
1.
a. Is this trait dominant or recessive?
Recessive
b. Circle the section of the pedigree that you used to determine dominant and recessive.
c. How many generations are shown?
4
d. List the genotype for as many individuals as possible.
2.
a. Is this trait dominant or recessive?
Dominant
b. Circle the section of the pedigree that you used to determine dominant and recessive.
c. How many generations are shown?
4
d. List the genotype for as many individuals as possible.
3.
a. Is this trait dominant or recessive?
This trait could be either dominant or recessive.
b. Circle the section of the pedigree that you used to determine dominant and recessive.
c. How many generations are shown?
4
d. List the genotype for as many individuals as possible.
4.
a. Is this trait dominant or recessive?
Recessive
b. Circle the section of the pedigree that you used to determine dominant and recessive.
c. How many generations are shown?
3
d. List the genotype for as many individuals as possible.
5.
a. What does a double line in a pedigree indicate? (see # 1 and 3)
A double line indicates that the mating pair is already genetically related (inbreeding).
b. From a genetics perspective, why can a “double line” relationship be dangerous?
A double line can be dangerous because it increases the chance that both parents could be carriers of (or
have) a genetic disorder and are more likely to pass it on to their offspring.
6.
Draw a pedigree for your (or a friends’) family including at least 3 generations.
Answers will vary.