Name______________________________________________
Mead Genetics
Lap 2 Extensions, Exceptions and Influence of Sex
Lesson 1: Problem Set 5.1
Suggested Practice Problems on page 109:
Review Questions #1-5 and Applied Questions #1, 4-6 (answers A-6)
Before attempting this problem set, I recommend completing the practice problems from the text.
These all have answers in the back of your book. You can check to be sure you understand the work
before submitting this problem set.
1. Give the correct phenomena responsible for the following changes to the Mendelian ratios (some
may have more than one answer):
a. Ratio of 2:1 due to a genotype (progeny class) being eliminated
b. Third phenotype possible that is a combination (blend or distinct) of the other two
phenotypes (2 answers)
c. Multiple phenotypes that can show both codominance and complete dominance
2. Give the correct phenomena responsible for the following scenarios:
a. Affects of this genetic disease are seen in the digestive, respiratory and skeletal system
b. Severity of PKU can affect the diet that is used in treatment
c. A child is found to carry a dominant allele trait, but neither parent appears to carry the
trait
d. In mice, 2 genes are involved in determining coat color
e. Off spring are 33% white fur and 66% brown fur
f.
A disease appears in three generations of a family, because all are living in a house
exposed to mold
g. Inherited arthritis can vary in the number of joint affected and the severity of the pain
experienced in different individuals affected
h. Two hearing impaired people marry, but their offspring has a low chance of inheriting a
disorder because the genetic cause of each parent’s hearing loss is different
3. Give the all genotypes possible for the following blood types
a. Type O
b. Type A
c. Type B
d. Type AB
4. Jim has type O blood. His parents have type A and B. Janet has type A blood. Her parents have
type O and A. What is the probability that Jim and Janet’s child would have the following types?
Give answer as a percent.
a. Type O
b. Type A
c. Type B
d. Type AB
5. Given the following information, answer the questions below:
Alleles
Gentoypes
h = hair
HH
H= hairless
Hh
hh
Phenotypes
lethal
Mexican hairless
hairy
a. If two hairless dogs breed, what is the genotypic raito?
b. If two hairless dogs breed, what is the phenotypic ratio?
c. If two hairy dogs breed, what is the genotypic ratio?
d. If two hairy dogs breed, what is the phenotypic raito?
e. If one hairy dog and one hairless dog breed, what is the genotypic ratio?
f.
If one hairy dog and one hairless dog breed, what is the phenotypic ratio?
6. One person who is heterozygous for familial hypercholesterolemia is married to a person that has
no evidence of the disorder. What is the probability that their child will have the most severe form
of the disorder? Give answer as a percent.