Chapter 12 “Patterns of Heredity and Human Genetics” Carrier Pedigree

Name: ___________________________________________________
Biology G
Period: _______
Chapter 12 “Patterns of Heredity and Human Genetics”
Vocabulary Section 12.1
Carrier
Pedigree
Vocabulary Section 12.2
Autosomes
Codominant
Alleles
Incomplete
Dominance
Multiple Alleles
Polygenic
Inheritance
Sex
Chromosomes
Sex-linked
Traits
Vocabulary Section 12.3
Blood Typing
Karyotyping
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Section 12.1 – Mendelian Inheritance of Human Traits
Pedigree Chart
KEY
Parents:
Offspring:
Has trait:
Generations: I, II, III, IV
Individuals: 1, 2, 3, …
Directions: Use the above pedigree to answer the questions below.
1. What gender is I-1 and II-3? __________________
2. What gender is I-2 and III-6? __________________
3. Is the trait being studied dominant or recessive? How do you know? _____________
____________________________________________________________________
4. What is the likely genotype of III-3? ______________________
5. What is the likely genotype of IV-4? ______________________
6. Is II-1 a carrier for the recessive allele? Explain? ______________________________
_____________________________________________________________________
7. Is III-7 a carrier for the recessive allele? Explain? ______________________________
_____________________________________________________________________
8. What is the likelihood that III-3 and III-4 will produce an individual
with the trait being studied? Draw a Punnett Square to show
your work.
________________________________________
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Section 12.1 – Mendelian Inheritance of Human Traits
Section 12.2 – When Heredity Follows Different Rules
Directions: Match the each item in Column A with correct letter from Column B.
Column A
Column B
1. _____ Recessive disorder that results in the
a. cystic fibrosis
absence of an enzyme required to break down
lipids.
b. simple dominant traits
2. _____ Lethal genetic disorder which occurs between
ages 30 and 50 that caused by a dominant allele.
c. Tay-Sachs disease
3. _____ Recessive disorder that results in thick mucus
in lungs.
d. Huntington’s disease
4. _____ Recessive disorder that results from enzyme
not converting PHE into another amino acid.
e. phenylketonuria
5. _____ Widow’s peak, hitch hiker’s thumb, and cleft
chin are examples.
Directions: Determine if the statement is true. If it is not, rewrite the italicized part to make it true.
6. _____ Traits controlled by more than 2 alleles are said to have multiple alleles.
7. _____ In humans, there are 23 pairs of matching homologous chromosomes called autosomes.
8. _____ Two chromosomes called sex chromosomes determine the sex of an individual.
9. _____ The sex chromosomes of a human male are XX, while for a female, they are XY.
10. _____ Traits controlled by genes located on sex chromosomes are called sex-linked traits.
Directions: Answer the following questions.
11. Complete the Punnett square for a cross between a homozygous red-flowered snapdragon (RR)
and a homozygous white-flowered snapdragon (R’R’).

Genotypes
RR: __________
Phenotypes
Red: _________
R’R’: __________
White: _________
RR’: __________
Pink: ________
What type of inheritance pattern is this – multiple allele,
codominance, incomplete dominance, or polygenic traits?
12. Complete a Punnett square for a cross between a black chicken (BB) and a white chicken (WW).

Genotypes
BB: __________
Phenotypes
black: _________
WW: __________
white: _________
BW: __________
checkered: ________
What type of inheritance pattern is this – multiple allele,
codominance, incomplete dominance, or polygenic traits?
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Section 12.3 – Complex Inheritance of Human Traits
Directions: Complete the table by filling in the missing information.
Genotypes
Phenotypes
AA or ________
BB or ________
Donate to
Receive from
Type A
Type A
Type O
Type B
Type AB
Type O
Type O
Directions: Complete each statement by using the words/phrases below.
A and B
can
multiple allele
AB
cannot
O
B
codominant
blood transfusion
5. Blood groups are a classic example of _____________________________ inheritance pattern.
6. The alleles _____________________________ are always both expressed.
7. The alleles A and B are ________________________, meaning they are always both expressed.
8. A and B are dominant to ______________.
9. Blood typing is necessary before a person can receive a ______________________________.
10. A child who inherits A from his mother and B from his father will have type ___________ blood.
11. A child whose parents have type BO and type BB will have type ____________ blood.
12. If a woman with blood type A has a baby with blood type AB, a man with blood type O
______________ be the father.
13. Blood tests _________________ be used to prove that a certain man is the father of a child.
Directions: Examine the karyotypes below to determine the gender of the person and if the karyotype
is normal or abnormal.
14. _______________________________
15. ________________________________
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Section 12.3 – Complex Inheritance of Human Traits
Using Genetics to Help Solve Mysteries
ABO blood type in humans is determined by 3 alleles: A, B and O. A and B are codominant alleles. A
and B are dominant to O. Four possible phenotypes or blood types (A, B, AB and O) are possible
when these alleles are combined. Using this information, give a possible solution for the following
problem.
Problem: Four newborn babies in the delivery room of a hospital at the same time were mixed up by
the nurse who attached the wristbands. The blood types of the four babies were known to be A, B,
AB and O. How did the doctors find out which baby belongs to which set of parents? They first
determined the parents blood type. Parents #1 had blood types O and AB; Parents #2 had blood
types AB and B; Parents #3 both had blood type ); and Parents #4 had blood types O and A. It is up
to you to figure out which set of parents belong to which newborn.
Solution: Use the Punnett squares to determine possible genotypes of offspring. Then write the
parents of each baby.
Parents #1
Parents #2
Parents #3
Parents #4
1. Baby with type AB blood = Parents # ___________
2. Baby with type B blood = Parents # __________
3. Baby with type A blood = Parents # ___________
4. Baby with type O blood = Parents # __________
Directions: Use the words below to fill in the blanks.
codominance
heterozygous
multiple alleles
O
5. A and B alleles are expressed equally which is an example of _____________________.
6. _____________ allele is the recessive trait.
7. This trait is controlled by 3 alleles. This is an example of _______________________________.
8. A person with genotype AO is ______________________________ for the trait.
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Chapter 12.3 Complex Inheritance of Human Traits
Directions: Read the passage below, which covers topics from your textbook.
Sex-linked traits are primarily found only on the X chromosome. Since they are on the X
chromosome, they are called X-linked. One form of colorblindness is a recessive X-linked
disorder in which an individual cannot distinguish certain colors. Although many forms of
colorblindness exist, the most common is the inability to distinguish red and green. About 8
percent of males are colorblind.
Hemophilia is another recessive X-linked disease that occurs almost exclusively in males.
This disorder impairs the ability of blood to clot following a cut, bruise, or other injury.
Another recessive X-linked trait in humans is Duchenne muscular dystrophy, a form of
muscular dystrophy that weakens and progressively destroys muscle tissue.
Directions: Use the passage to complete the table below describing X-linked disorders.
Disorder
Symptom
1.
Colorblindness
Impaired ability of blood to clot following a cut, bruise, or other injury
2.
3.
Duchenne muscular dystrophy
Directions: Circle the letter of the phrase that best answers the question.
4. How are all three disorders that are in the passage alike?
a. All occur mainly in males.
b. All are recessive traits.
c. About 8 percent of the population is affected by these disorders.
d. All affect muscle tissue.
5. X-linked traits are also called
a. recessive traits
b. dominant traits
c. sex-linked traits
d. carrier traits
6. Since about 8 percent of the male population is colorblind, you would predict t\the percent of the
female population to be
a. higher
b. lower
c. same
d. equal
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Chapter 12 Assessment and Vocabulary
1. The 23rd pair of chromosomes that differ in males and females are called
a. autosomes
b. sex chromosomes
c. multiple alleles
d. polygenic traits
2. Another name for a heterozygous individual is
a. homozygous
b. autosomes
c. pedigree
d. carrier
3. A graphic representation of an individual’s family tree is
a. a pedigree
b. a kayrotype
c. a phenotype
d. a table
4. When roan cattle mate, 25% of the offspring are red, 50% are roan, and 25% are white. When
looking at the roan cattle, it is observed that they have some red hairs and some white hairs. This
is an example of
a. multiple alleles
b. sex-linked genes
c. codominant alleles
d. incomplete dominant alleles
Directions: Use the pedigree to the right to answer questions 5-7. The trait being studied is for
hemophilia. Unshaded individuals are homozygous dominant while shaded individuals are
homozygous recessive.
5. How are individuals I-1 and III-2 related?
a. Grandfather-granddaughter
b. Grandmother-grandson
c. Great aunt-nephew
d. Mother-son
6. For the trait being studied in the pedigree, individuals
II-1 and II-4 can be classified as
a. homozygous dominant
b. mutants
c. homozygous recessive
d. carriers
7. What type of inheritance pattern does the pedigree
show?
a. Incomplete dominance
b. Multiple alleles
c. Codominance
d. Sex-linked trait
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Chapter 12 Scientific Method and Graphing
1. Smithers has been having trouble with fruit flies in his home. He remembered something
about them from Biology class and genetics. He remembers that they were
used to study inheritance of traits because they reproduce so quickly. This
is his problem – he can’t get rid of them. He wants to try a fruit fly spray
called RIDD to see if it gets rid of the flies. He has 2 groups: Group A has
bananas in a bowl while Group B has bananas in a bowl with the spray put
on the bananas. After 6 hours, Smithers counts how many fruit flies there
are: Group A – 1, Group B – 5; after 12 hours: Group A – 2, Group B 20; after 24 hours:
Group A – 2, Group B – 40; after 36 hours: Group A – 0, Group B – 55; and after 48
hours: Group A – 0, Group – 70.
a. What is the Control Group? _______________________________
b. What is the Independent Variable? _____________________________________
c. What is the Dependent Variable? ______________________________________
d. What should Smithers' conclusion be?
__________________________________________________________________
e. Graph the data below using 2 lines. Make sure to include title and label axes.
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