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Name ____________________________
KEY
PRACTICE TEST CHAPTER 11
Period ____ Date __________ Seat ____
B
______
1.
Different forms of a gene are called
a.
C
______
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
b. actual outcome of a cross
d. result of meiosis
genetics
b. heredity
c. phenotype
d. genotype
complete dominance
polygenic dominance
b. codominance
d. multiple alleles
one haploid gamete
four diploid gametes
b. three diploid gametes
d. four haploid gametes
It doubles
b. It stays the same
c. It halves
d. It becomes diploid
3:1
b. 1 : 3 : 1
c. 1 : 2
d. 3 : 4
prophase I
b. metaphase I
c. anaphase I
D. telophase II
Two pink-flowering plants are crossed. The offspring flower as follows: 25% red, 25% white,
and 50% pink. What pattern of inheritance does flower color in these flowers follow?
a.
B
______
probable outcome of a cross
result of incomplete dominance
During which phase of meiosis is the chromosome number reduced?
a.
D
______
d. dominant
Which phenotypic ratio did Mendel find in his F2 Generation from the parental cross TT x tt?
a.
D
______
c. homozygous
What happens to the chromosome number during meiosis?
a.
A
______
b. heterozygous
Unlike mitosis, meiosis in male mammals results in the formation of
a.
c.
C
______
hybrid
A situation in which a gene has more than two alleles is known as
a.
c.
D
______
d. recessive factors
The physical characteristics of an organism are called its
a.
D
______
c. dominant factors
A Punnett square is used to determine the
a.
c.
C
______
b. alleles
Organisms that have two identical alleles for a particular trait are said to be
a.
A
______
hybrids
dominance
b. multiple alleles
c. polygenic traits
d. incomplete dominance
c. gametes
d. phenotype
The genetic makeup of an organism is its
a.
heredity
b. genotype
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PRACTICE TEST CHAPTER 11
B
______
12.
Alleles are first separated from each other during the process of
a. cytokinesis
D
______
13.
b. meiosis I
c. meiosis II
D. metaphase II
Which of the following is NOT one of Gregor Mendel’s principles?
a.
b.
c.
d.
The alleles for different genes usually segregate independently.
Some forms of a gene may be dominant.
The inheritance of characteristics is determined by factors (genes).
Crossing-over occurs during meiosis.
Questions 14-16
The Punnett square below shows a cross between two pea plants each with round seeds.
A
______
14.
15.
R
RR
Rr
R
RR
Rr
b. RRrr
c. rr
d. RR
Which statement is true about the cross in the Punnett square?
a.
b.
c.
d.
D
______
16.
?
The unknown genotype is
a. Rr
C
______
?
Both parents are heterozygous for the trait.
Both parents are homozygous for the trait.
One parent is heterozygous and the other is homozygous for the trait.
The trait is controlled by codominant alleles.
What percentage of the offspring of this cross will produce round sees?
a.
0%
b. 25%
c. 50%
d. 100%
17. Suppose Mendel crossed two pea plants and got both purple and white flowers. What could
have been the genotypes of the two original plants? What genotype could not have been present.


The original genotypes and the crosses could have been Pp x Pp or Pp x pp.
The genotype PP could not have been present; if it were, all the offspring would be tall.
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PRACTICE TEST CHAPTER 11
18. In guinea pigs, the allele for a rough coat (R) is dominant over the allele for a smooth coat (r).
A heterozygous guinea pig and a homozygous recessive guinea pig have a total of nine offspring.
Is it possible for all of the offspring to have smooth coats? Explain your answer.
The result of each fertilization event is independent of any previous fertilization
event. It is possible for all nine offspring to have smooth coats, although it would be
rare (1 chance out of 512). This would be equivalent to getting heads 9 times in a row
when flipping a coin (29). For all nine offspring to have smooth coats, each would
need to receive a recessive allele from both its parents.
In pea plants, the coat, or covering, of the seed is either smooth or wrinkled. Suppose a researcher has two
plants—one that makes smooth seeds and another that makes wrinkled seeds. The researcher crosses the
wrinkled-seed plants and the smooth-seed plants, obtaining the following data. Use the data to answer
questions 19 and 20.
19. Mendel knew that the allele for smooth (R) seeds was dominant over the allele for wrinkled (r) seeds.
If this cross was RR x rr, what numbers would fill the middle column?
RESULT OF SEED EXPERIMENT
Phenotype
Number of Plants in the F1 Generation
Expected
Observed
Smooth seeds
66
63
Wrinkled seeds
66
69
20. Are the observed numbers consistent with the hypothesis that the cross is Rr x rr? Explain your answer.
Yes, the observed numbers are close to the expected values. No other cross would
predict a ratio close to 50% for each trait.
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PRACTICE TEST CHAPTER 11
Questions 21 and 22 refer to Figure 11-1.
Chromosomes are made of many genes linked together. Gene maps, like the one shown in figure 11-1, show
how far apart these genes are from each other. For example, the alleles for black body and reduced bristles are
located close together, while the alleles for dumpy wing and brown eye are farther apart.
21. Which trait is most likely linked to having speckled wings in the fruit fly in Figure 11-1? Explain why.
Any fruit fly that inherits speckled wings would most likely inherit brown eyes too. The
reason is that these two genes are found very close to each other on chromosome #2,
reducing the chances that they will be separated by a crossing-over event.
22. Which trait is least likely to be linked to having speckled wings in the fruit fly? Explain why.
The allele for star eye would be the least likely to be inherited along with the speckled
wing because the two alleles are at opposite ends of the chromosome. This large distance
increases the chances that the alleles will be separated by a crossing-over event.
Exact Location on Chromosome
Chromosome 2
0.0
1.3
13.0
Star eye
Dumpy wing
31.0
Dachs (short legs)
48.5
51.0
Black body
Reduced bristles
54.5
55.0
Purple eyes
Light eye
67.0
75.5
Vestigial (small) wing
Curved wing
99.2
104.5
107.0
Arc (bent wings)
Brown eye
Speckled wing
10
20
30
40
50
60
70
80
90
100
110
23. Make a diagram modeling how crossing-over occurs between the chromatids of homologous
chromosomes.
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