AP Biology Pedigree Problem Set for Genetics Practice

AP Biology Pedigree Problem Set for Genetics Practice

The AP Biology Pedigree Problem Set focuses on genetics, specifically pedigree analysis and inheritance patterns. It includes various problems related to traits such as tongue rolling, blood types, earlobe attachment, dimples, hemophilia, and color-blindness. Designed for AP Biology students, this resource aids in understanding genetic inheritance and constructing pedigrees. It provides detailed scenarios that require students to determine genotypes and analyze family traits, making it an essential tool for exam preparation.

Key Points

  • Includes problems on tongue rolling and blood type inheritance.
  • Covers earlobe attachment and dimples in pedigree analysis.
  • Explores X-linked disorders like hemophilia and color-blindness.
  • Offers practice in constructing pedigrees for genetic traits.
  • newtopiccyclegrowin
114
/ 5
AP Biology Pedigree Problem Set
NOTE: Some genotypes cannot be determined in these problems- write ALL possible for those.
1. Jim and Jill are both tongue-rollers (TT or Tt – you determine which). They have 4
children. The children are shown in the pedigree below. Write in the genotype for all
individuals on the pedigree. NOTE: In this pedigree, the individuals are only shown as
having the trait- it is up to you to determine if they are homozygous or heterozygous-
half-shaded boxes are NOT being used for this example.
2. Adriana and Javier have 3 children. Adriana has type AB blood and Javier has type B
blood. List the missing genotypes for the pedigree shown below. HINT: Work from
bottom to top.
I
A
I
B
I
B
I
B
I
B
i
Blood Genotypes
A = I
A
I
A
, I
A
i
B = I
B
I
B
, I
B
i
AB = I
A
I
B
0 = ii
3. Use the information you have learned about pedigrees to construct a pedigree for the
following family. Use E for earlobe attachment. Shade the whole symbol for dominant
traits and half of the symbol for heterozygous traits. Unattached earlobes are
dominant to attached.
a. Father = heterozygous for unattached earlobes.
b. Mother = homozygous recessive for attached earlobes.
c. Male Child 1 = heterozygous
d. Male Child 2 = homozygous recessive
e. Female Child = heterozygous
4. Construct a pedigree for the following family. You may have to work backwards on some
of the individuals. Fill in the missing phenotypes for individuals in the list below. You
have been given enough clues to fill the genotypes (remember- if you cannot determine
if they are homozygous dominant or heterozygous, then write both).
a. Use a ruler to make the diagram neat. Shade the whole symbol for dominant
individuals and shade half of the symbol for heterozygous individuals and there is
no shading for recessive. Use the back or another sheet of paper if you need more
room.
b. Dimples (D) are dominant over no dimples.
c. John = Dimples
d. Mary = Dimples
e. Luke (child of John and Mary) = Dimples (homozygous)
f. Sarah (child of John and Mary) = No Dimples
g. Mark (child of John and Mary) = Dimples
h. Elizabeth (wife of Luke) = No Dimples
i. Johnny (child of Luke and Elizabeth) = ? _____________________
j. Matthew (child of Luke and Elizabeth) = ? ____________________
k. Ann (child of Luke and Elizabeth) = ? ________________________
l. Margaret (wife of Mark) = Dimples
m. Katherine (child of Margaret and Mark) = heterozygous dimples
n. Grace (child of Margaret and Mark) = homozygous dimples
o. Claire (child of Margaret and Mark) = Dimples
p. Michael (husband of Claire) = No Dimples
q. Caroline (child of Claire and Michael) = Heterozygous Dimples
5. A man and woman marry. They have five children, 2 girls and 3 boys. The mother is a
carrier of hemophilia, an X-linked disorder. She passes the gene on to two of the boys
who died in childhood and one of the daughters is also a carrier. Both daughters marry
men without hemophilia and have 3 children (2 boys and a girl). The carrier daughter
has one son with hemophilia. One of the non-carrier daughter’s sons marries a woman
who is a carrier and they have twin daughters. Construct a pedigree to show the
inheritance pattern of this family. What is the percent chance that each
daughter will also be a carrier?
Type
A
6. The great-great maternal grandmother of a boy was a carrier for color-blindness, an X-
linked disorder. His great uncle on his mother’s side was colorblind but this great
uncle’s father was unaffected. The boy’s mother has 2 brothers (1 colorblind, 1
unaffected) and 1 sister (unaffected). The boy’s grandmother on his mother’s side had 1
brother who was colorblind and 3 sisters. Two of these sisters were unaffected and one
was a carrier. The boy’s great grandmother on his mother’s side had 4 sisters. The boy
has one unaffected sister and he is colorblind. Construct a pedigree to show the
inheritance pattern of this family. What is the probability of the boy’s sons being
colorblind if he marries a non-carrier?
7. An unaffected man marries a woman who is a carrier for Duchenne Muscular
Dystrophy, which is attributed to an X-linked gene. They have four children, one with
Duchenne, one carrier daughter and a daughter and son who are unaffected. The child
with Duchenne Muscular Dystrophy dies in childhood. The carrier daughter marries
and has three children of her own, two of which are carriers and one of which is
unaffected. Construct a pedigree to show the inheritance pattern of this family. What
is the most likely sex of these two carrier children given the fact that they
are unaffected by the X-linked gene?
X
H
= normal
X
h
= hemophilia (a genetic disease or abnormality)
Y = Y chromosome (males only)
X
C
= normal
X
c
= Colorblind (a genetic disease or abnormality)
Y = Y chromosome (males only)
X
D
= normal
X
d
= Duchenne MD (a genetic disease or abnormality)
Y = Y chromosome (males only)
/ 5
End of Document
114
You May Also Like

FAQs of AP Biology Pedigree Problem Set for Genetics Practice

What is the significance of pedigree analysis in genetics?
Pedigree analysis is crucial in genetics as it helps trace the inheritance patterns of traits through generations. By analyzing family trees, geneticists can determine how traits are passed down, identify carriers of genetic disorders, and predict the likelihood of traits appearing in future generations. This method is particularly useful for understanding complex traits influenced by multiple genes and environmental factors.
How do you determine genotypes from a pedigree?
Determining genotypes from a pedigree involves analyzing the phenotypes of individuals and their relationships. For dominant traits, individuals showing the trait can be either homozygous dominant or heterozygous, while those without the trait are homozygous recessive. By using the information about affected and unaffected individuals, one can deduce possible genotypes through logical reasoning and understanding of Mendelian inheritance.
What are some examples of traits analyzed in this problem set?
The problem set analyzes traits such as tongue rolling, blood types (A, B, AB, O), earlobe attachment (attached vs. unattached), and dimples. It also covers X-linked conditions like hemophilia and color-blindness, providing a comprehensive overview of how these traits are inherited. Each example illustrates the application of pedigree analysis in real-world genetic scenarios.
What role do carriers play in genetic inheritance?
Carriers are individuals who possess one copy of a recessive allele for a genetic trait but do not express the trait themselves. In the context of X-linked disorders, such as hemophilia, female carriers can pass the allele to their offspring, potentially leading to affected males. Understanding the role of carriers is essential for predicting the inheritance of genetic disorders and assessing risks in family planning.
How does this problem set help with AP Biology exam preparation?
This problem set is designed to reinforce key concepts in genetics and pedigree analysis, which are critical for the AP Biology exam. By working through various scenarios, students practice applying Mendelian principles, understanding inheritance patterns, and constructing pedigrees. These skills are essential for answering exam questions related to genetics and can significantly enhance a student's performance.

Related of AP Biology Pedigree Problem Set for Genetics Practice