Module Seven Lesson Three Practice Name_______________________
Genetics Review Problems for Test
Highlight the correct answer and show all punnett squares.
1. When roan cattle are mated, 25% of the offspring are red, 50% are roan, and 25% are white. Upon examination, it can be seen that the coat of roan cow consists of both red and white hairs.
What controls this trait?
A. Multiple alleles
B. Co-dominant alleles
C. Sex-linked genes
D. Polygenic inheritance
2. A cross between a white rooster and a black hen results in
100% blue Andalusia offspring. When two of the blue offspring are mated, what is the probable phenotypic ratio seen in their offspring.
A. 100% blue
B. 75% black 25% white
C. 75% blue 25% white
D. 25% black 50% blue 25% white.
3. A child is diagnosed with a rare genetic disease. Neither parent has the disease. How might the child have inherited the disorder?
A. The disorder is dominant and was carried by a parent
B. The disorder is recessive and carried by both parents
C. The disorder is sex-linked and inherited only from the father
D. The disorder could occur only as a mutation in the child because neither parent had the disease
4. A man heterozygous for blood type A marries a woman heterozygous for blood type B. what is the chance their first child will have type O blood?
A. 0%
B. 25%
C. 50%
D. 75%
5. How many chromosomes are shown in a normal human karyotype?
A. 3
B. 23
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Module Seven Lesson Three Practice Name_______________________
C. 44
D. 46
6. Which of the following can be observed in a karyotype?
A. A change in a DNA base
B. An extra chromosome
C. Genes
D. Allels
7. What is the failure of homologous chromosomes to separate during meiosis called?
A. Nondisjunction
B. Translocation
C. Cystic fibrosis
D. Down syndrome
8. As a women ages what happens to the likelihood of having a baby with down syndrome
A. It increases
B. It decreases
C. It does not change
9. If a red snapdragon is crossed with a pink snapdragon, what are the expected results?
A. 50% red, 50% pink
B. 100% red
C. 25% red, 50% pink, 25% white
D. 50% red, 50% white
10. A black Guinea pig is mated with a white guinea pig. If all of the offspring are black, what are most likely the genotypes of the parents?
A. BB x bb
B. Bb x bb
C. Bb x Bb
D. Bb x BB
11. A man with blood type O marries a woman with blood type
AB. What are all possible blood types of their children?
A. A, B, or O
B. A or B
C. AB or O
D. A, B, AB, or, O
12. A child has blood type O. Which of the following couples are most likely the child’s parents based on their blood types?
A. Man with AB and woman with O
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Module Seven Lesson Three Practice Name_______________________
B. Man with B and woman with AB
C. Man with AB and woman with A
D. Man with A and woman with B
13. In a genetic laboratory, two heterogeneous tall plants are crossed. If tall is dominant over short, what are the expected phenotypic results?
A. 100% tall
B. 75% tall, 25% short
C. 50% tall, 50% short
14. Which genotype is used in a test cross?
A. Homozygous dominant
B. Heterozygous dominant
C. Homozygous recessive
15.
D. Heterozygous recessive
When viewing a karyotype to detect genetic disorders, which of the following would be a concern?
A. Chromosomes of different lengths
B. Two X chromosomes
C. Twenty- three pairs of chromosomes
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D. Three chromosomes in any one set
A pea plant has purple flowers. The purple flowered plant is crossed with a homozygous recessive white flowering plant.
The cross produces some purple and some white flowers. What are the genotypes of the parent cross?
A. Pp x Pp
B. PP x pp
C. PP x Pp
D. Pp x pp
In guinea pigs, black fur is dominate over white fur. A heterozygous black guinea pig is mated with a white one.
1. If a female had a liter of 8 baby guinea pigs, how many would be expected to have white fur?
A. 4
B. 1
C. 2
D. 8
2. What is the ratio of black to white guinea pigs?
A. 1:1
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Module Seven Lesson Three Practice Name_______________________
B. 3:1
C. 1:3
D. 4:0
3. What percent of the offspring will be heterozygous?
A. 25%
B. 50%
C. 75%
D. 100%
A dominant gene produces wired haired texture in dogs. Its recessive allele produces smooth hair. Cross two heterozygous wire haired dogs.
1. What percent of offspring are pure for smooth hair?
A. 25%
B. 50%
C. 75%
D. 100%
2. What is the ratio of wire hair to smooth?
A. 3:1
B. 1:2:1
C. 1:1
D. 1:3
3. Which of the following best describes the probable results from the cross?
A. 3 genotypes, 2 phenotypes
B. 2 genotypes, 3 phenotypes
C. 2 genotypes, 2 phenotypes
D. 3 genotypes, 3 phenotypes
Purple flowers are dominant over white flowers. A pure purpled flowered plant is crossed with a homozygous recessive plant.
1. What would be the expected outcome?
A. 124 purple flowers and 126 white flowers
B. 234 purple flowers
C. 145 purple flowers and 50 white flowers
D. 48 purple flowers and 152 white flowers
2. What percent of the offspring are homozygous?
A. 0%
B. 25%
C. 50%
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Module Seven Lesson Three Practice Name_______________________
D. 100%
If red snapdragon flowers are crossed with white snapdragons, pink snapdragon flowers are produced.
1. What kind of dominance is shown by snapdragons?
A. Complete
B. Incomplete
C. Co-Dominance
D. Hybridization
2. If two pink snapdragons are crossed, what are the expected phenotypic results?
A. ¼ red, ½ pink, ¼ white
B. ¾ red, ¼ white
C. ¼ red, ¾ white
D. ½ red, ½ white
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