Applied Genetics Practice Exam

1. Having more or less than the average number of chromosomes can result in

Fraternal twins

Identical twins

Cloned cells

Genetic disorders

Having more or less than the average number of chromosomes can lead to genetic disorders. This is because the number and structure of chromosomes play a crucial role in the normal functioning of genes and the overall genetic makeup of an individual. Any deviation from the normal number of chromosomes can disrupt the balance of genetic material, leading to various abnormalities and health conditions.

Explanation

Having more or less than the average number of chromosomes can lead to genetic disorders. This is because the number and structure of chromosomes play a crucial role in the normal functioning of genes and the overall genetic makeup of an individual. Any deviation from the normal number of chromosomes can disrupt the balance of genetic material, leading to various abnormalities and health conditions.

2. A change in a gene is called

Genetic engineering

A mutation

A gene

A pedigree

A change in a gene is referred to as a mutation. Mutations can occur naturally or can be induced through various factors such as exposure to radiation or chemicals. These changes can alter the DNA sequence of a gene, leading to changes in the protein it codes for. Mutations can have different effects, ranging from no impact to causing genetic disorders or diseases. Therefore, "a mutation" is the correct answer as it accurately describes the phenomenon of a change in a gene.

Explanation

A change in a gene is referred to as a mutation. Mutations can occur naturally or can be induced through various factors such as exposure to radiation or chemicals. These changes can alter the DNA sequence of a gene, leading to changes in the protein it codes for. Mutations can have different effects, ranging from no impact to causing genetic disorders or diseases. Therefore, "a mutation" is the correct answer as it accurately describes the phenomenon of a change in a gene.

3. A chart that traces an inherited trait through several generations is called a

Pedigree

Karyotype

Family tree

Gene chart

A chart that traces an inherited trait through several generations is called a pedigree. This type of chart is commonly used in genetics to analyze the inheritance patterns of specific traits or diseases within a family. It helps to visualize the relationships between family members and track the presence or absence of a trait over time. By studying pedigrees, scientists can better understand how traits are passed down from one generation to the next and identify patterns of inheritance.

Explanation

A chart that traces an inherited trait through several generations is called a pedigree. This type of chart is commonly used in genetics to analyze the inheritance patterns of specific traits or diseases within a family. It helps to visualize the relationships between family members and track the presence or absence of a trait over time. By studying pedigrees, scientists can better understand how traits are passed down from one generation to the next and identify patterns of inheritance.

4. In a pedigree, a half shaded individual represents a

Recessive trait

Dominant trait

Carrier

Unaffected individual

A half shaded individual in a pedigree represents a carrier. A carrier is an individual who carries a recessive trait but does not express it themselves. They can pass on the trait to their offspring, who may or may not express the trait depending on whether they inherit another copy of the recessive allele.

Explanation

A half shaded individual in a pedigree represents a carrier. A carrier is an individual who carries a recessive trait but does not express it themselves. They can pass on the trait to their offspring, who may or may not express the trait depending on whether they inherit another copy of the recessive allele.

5. Which of these is not a benefit of genetically modified organisms?

They increase the food supply

They help with scientific research of valuable proteins

They produce plants that contain their own herbicides and pesticides

They increase the risk of allergies in children

Genetically modified organisms (GMOs) have several benefits, including increasing the food supply by improving crop yield and resistance to pests and diseases. They also aid in scientific research by producing valuable proteins. Additionally, GMOs can be engineered to contain their own herbicides and pesticides, reducing the need for external chemical applications. However, one potential drawback of GMOs is that they may increase the risk of allergies in children.

Explanation

Genetically modified organisms (GMOs) have several benefits, including increasing the food supply by improving crop yield and resistance to pests and diseases. They also aid in scientific research by producing valuable proteins. Additionally, GMOs can be engineered to contain their own herbicides and pesticides, reducing the need for external chemical applications. However, one potential drawback of GMOs is that they may increase the risk of allergies in children.

6. Genetic disorders are commonly inherited and are transferred from one generation to the next. However, it is possible to get a genetic disorder without it "running in the family". How does this occur?

A mutation in a gene causes the appearance of a disorder.

Genes are transferred from one individual to another through genetic engineering

Cloning

Genetic disorders can only be only be inherited

A mutation in a gene can cause the appearance of a genetic disorder even if it does not run in the family. Mutations can occur spontaneously during DNA replication or as a result of environmental factors such as radiation or exposure to certain chemicals. These mutations can alter the normal function of a gene, leading to the development of a genetic disorder. Therefore, it is possible for someone to have a genetic disorder without it being inherited from their family.

Explanation

A mutation in a gene can cause the appearance of a genetic disorder even if it does not run in the family. Mutations can occur spontaneously during DNA replication or as a result of environmental factors such as radiation or exposure to certain chemicals. These mutations can alter the normal function of a gene, leading to the development of a genetic disorder. Therefore, it is possible for someone to have a genetic disorder without it being inherited from their family.

7.

The chart above tells you that the disorder being traced is a

Dominant disorder

Recessive disorder

Autosomal disorder

None of the above

Based on the information provided in the chart, it can be inferred that the disorder being traced is a recessive disorder. This can be determined because recessive disorders require both copies of the gene to be affected in order for the disorder to be expressed. If it were a dominant disorder, only one copy of the gene would need to be affected. The chart likely shows a pattern of inheritance consistent with a recessive disorder, such as the disorder skipping generations or appearing in unaffected parents who are carriers of the gene.

Explanation

Based on the information provided in the chart, it can be inferred that the disorder being traced is a recessive disorder. This can be determined because recessive disorders require both copies of the gene to be affected in order for the disorder to be expressed. If it were a dominant disorder, only one copy of the gene would need to be affected. The chart likely shows a pattern of inheritance consistent with a recessive disorder, such as the disorder skipping generations or appearing in unaffected parents who are carriers of the gene.

8.
A baby was found abandoned on the steps of the local hospital. Items that were located in the baby's carseat led to the identification of five individuals who were potential relatives of the child. Police took samples from the child (sample A) and five women who could be the child's mother (samples B-F). Based on the picture, which sample is most likely the mother of the child?

Sample B

Sample C

Sample D

Sample E

Sample F

not-available-via-ai

Explanation

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9. A farmer grows a mutant form of corn on three of six fields on his farm. On the other three fields, he grows organic corn for the farmer's market. What is one possible disadvantage he will face in this process (the best possible answer)?

Increase possibility of allergies

Increase in profit because he is producing twice the amount of corn

Herbicide resistant corn

The possibility of cross-pollination destroying both crops

The farmer may face the possibility of cross-pollination destroying both crops.

Explanation

The farmer may face the possibility of cross-pollination destroying both crops.

10.

The above image shows a picture of what process?

Bacterial conjugation

Genetic engineering

Recombinant DNA

Gel electrophoresis

The image shows a picture of gel electrophoresis, a technique used in molecular biology to separate DNA, RNA, or proteins based on their size and charge. In gel electrophoresis, a sample is loaded onto a gel matrix and an electric current is applied, causing the molecules to migrate through the gel. The smaller molecules move faster and travel further, resulting in distinct bands or patterns that can be visualized and analyzed. This technique is commonly used in genetic research, forensics, and medical diagnostics.

Explanation

The image shows a picture of gel electrophoresis, a technique used in molecular biology to separate DNA, RNA, or proteins based on their size and charge. In gel electrophoresis, a sample is loaded onto a gel matrix and an electric current is applied, causing the molecules to migrate through the gel. The smaller molecules move faster and travel further, resulting in distinct bands or patterns that can be visualized and analyzed. This technique is commonly used in genetic research, forensics, and medical diagnostics.

11. Male pattern baldness is a sex-linked trait. That means that it is most commonly passed from

Father to son

Mother to son

Father to daughter

Mother to daughter

Male pattern baldness is a sex-linked trait because it is primarily passed down from fathers to their sons. This is because the gene responsible for male pattern baldness is located on the X chromosome. Since males inherit one X chromosome from their mother and one Y chromosome from their father, they only need to receive the baldness gene from their father to exhibit the trait. However, females can also be carriers of the gene and pass it on to their sons.

Explanation

Male pattern baldness is a sex-linked trait because it is primarily passed down from fathers to their sons. This is because the gene responsible for male pattern baldness is located on the X chromosome. Since males inherit one X chromosome from their mother and one Y chromosome from their father, they only need to receive the baldness gene from their father to exhibit the trait. However, females can also be carriers of the gene and pass it on to their sons.

12.                                          "What is on the horizon for GMO's?"
    Combining genes from different organisms is known as recombinant DNA technology, and the resulting organism is said to be "genetically modified," "genetically engineered," or "transgenic." GM products (current or those in development) include medicines and vaccines, foods and food ingredients, feeds, and fibers. Locating genes for important traits—such as those conferring insect resistance or desired nutrients—is one of the most limiting steps in the process. However, genome sequencing and discovery programs for hundreds of organisms are generating detailed maps along with data-analyzing technologies to understand and use them. In 2006, 252 million acres of transgenic crops were planted in 22 countries by 10.3 million farmers. The majority of these crops were herbicide- and insect-resistant soybeans, corn, cotton, canola, and alfalfa. Other crops grown commercially or field-tested are a sweet potato resistant to a virus that could decimate most of the African harvest, rice with increased iron and vitamins that may alleviate chronic malnutrition in Asian countries, and a variety of plants able to survive weather extremes. On the horizon are bananas that produce human vaccines against infectious diseases such as hepatitis B; fish that mature more quickly; cows that are resistant to bovine spongiform encephalopathy (mad cow disease); fruit and nut trees that yield years earlier, and plants that produce new plastics with unique properties. In 2006, countries that grew 97% of the global transgenic crops were the United States (53%), Argentina (17%), Brazil (11%), Canada (6%), India (4%), China (3%), Paraguay (2%) and South Africa (1%). Although growth is expected to plateau in industrialized nations, it is increasing in developing countries. The next decade will see exponential progress in GM product development as researchers gain increasing and unprecedented access to genomic resources that are applicable to organisms beyond the scope of individual projects. Technologies for genetically modifying foods offer dramatic promise for meeting some of the 21st Century's greatest challenges. Like all new technologies, they also pose some risks, both known and unknown. Controversies surrounding GM foods and crops commonly focus on human and environmental safety, labeling and consumer choice, intellectual property rights, ethics, food security, poverty reduction, and environmental conservation (see GM Products: Benefits and Controversies, below).

Based on the information in the article, the following statement could be concluded

Genetically modified food can provide a great deal of scientific and agricultural advancements that would benefit countries

Many other countries will now test and use genetically modified crops to provide food for their people.

Genetic engineering is a difficult process and can be very expensive.

Genetic engineering can be used to cure "mad cow" disease.

The passage states that genetically modified organisms (GMOs) have the potential to provide solutions to challenges in the 21st century, such as meeting food security needs, reducing poverty, and conserving the environment. It also mentions various examples of GM products that are currently being developed or tested, such as crops with increased nutrients, plants that can survive extreme weather, and animals with desirable traits. Therefore, it can be concluded that genetically modified food can provide scientific and agricultural advancements that would benefit countries.

Explanation

The passage states that genetically modified organisms (GMOs) have the potential to provide solutions to challenges in the 21st century, such as meeting food security needs, reducing poverty, and conserving the environment. It also mentions various examples of GM products that are currently being developed or tested, such as crops with increased nutrients, plants that can survive extreme weather, and animals with desirable traits. Therefore, it can be concluded that genetically modified food can provide scientific and agricultural advancements that would benefit countries.

13. Which of the following would be the best reason for creating genetically modified animals

Scientists would be able to control the inheritance of desirable traits while "weeding out" traits that were undesirable

Genetically modified animals created in large numbers lower the cost of food and are more healthy

Genetically modified animals can be created much quicker in a lab than in nature

Genetically modified animals can create anti-biotic resistant strains of bacteria

Creating genetically modified animals allows scientists to have control over the inheritance of desirable traits and eliminate undesirable traits. This can lead to the development of animals with improved characteristics, such as increased resistance to diseases, higher productivity, or better nutritional value. By selectively manipulating the genes, scientists can enhance the overall quality and health of the animals. This can have significant benefits in fields like agriculture and medicine, where genetically modified animals can contribute to increased food production and the development of new treatments.

Explanation

Creating genetically modified animals allows scientists to have control over the inheritance of desirable traits and eliminate undesirable traits. This can lead to the development of animals with improved characteristics, such as increased resistance to diseases, higher productivity, or better nutritional value. By selectively manipulating the genes, scientists can enhance the overall quality and health of the animals. This can have significant benefits in fields like agriculture and medicine, where genetically modified animals can contribute to increased food production and the development of new treatments.

14. In chinchillas, grey fur (G) is dominat over white fur (g). What is the percentage of offspring that will have grey fur if a heterozygous dominant chinchilla is crossed with a homozygous dominant chinchilla?

0%

50%

75%

100%

When a heterozygous dominant chinchilla (Gg) is crossed with a homozygous dominant chinchilla (GG), the possible genotypes of the offspring are Gg and GG. Both of these genotypes have at least one dominant allele (G), which determines grey fur. Therefore, all the offspring will have grey fur. Hence, the percentage of offspring with grey fur is 100%.

Explanation

When a heterozygous dominant chinchilla (Gg) is crossed with a homozygous dominant chinchilla (GG), the possible genotypes of the offspring are Gg and GG. Both of these genotypes have at least one dominant allele (G), which determines grey fur. Therefore, all the offspring will have grey fur. Hence, the percentage of offspring with grey fur is 100%.

15.

The above pedigree is for albinism. Reading from your left to your right in the second row (first generation offspring), what is the genotype of the second sibling (daughter)?

AA

Aa

Albino

Unaffected

The given pedigree is for albinism, a genetic condition caused by a recessive allele. The second sibling (daughter) in the second row is unaffected by albinism, which means she does not have the condition. This suggests that she has at least one dominant allele, making her genotype Aa.

Explanation

The given pedigree is for albinism, a genetic condition caused by a recessive allele. The second sibling (daughter) in the second row is unaffected by albinism, which means she does not have the condition. This suggests that she has at least one dominant allele, making her genotype Aa.

16. Below is a pedigree for albinism. Based on the information, what type of trait is albinism?

Autosomal and recessive

Autosomal and dominant

Sex-linked and recessive

Sex-linked and dominant

Albinism is an autosomal and recessive trait because it is not linked to the sex chromosomes (X and Y) and requires two copies of the recessive allele to be expressed. This means that individuals can be carriers of the trait without showing any symptoms, and two carrier parents have a 25% chance of having an albino child.

Explanation

Albinism is an autosomal and recessive trait because it is not linked to the sex chromosomes (X and Y) and requires two copies of the recessive allele to be expressed. This means that individuals can be carriers of the trait without showing any symptoms, and two carrier parents have a 25% chance of having an albino child.

17. Cloning involves taking a cell from one organism, fusing it with the cell of another organism and then implanting it into the uterus of a "foster mother". The offspring is then genetically identical to the parent cell. In what other situation does this occur?

Meiosis

Mitosis

Identical twins

Fraternal twins

Mitosis is the correct answer because it is a process of cell division in which a single cell divides into two identical daughter cells. During mitosis, the genetic material is replicated and distributed equally between the two daughter cells, resulting in genetically identical cells. This is similar to cloning where the offspring is genetically identical to the parent cell. Meiosis, on the other hand, is a type of cell division that produces cells with half the number of chromosomes, leading to genetic variation. Identical twins occur when a single fertilized egg splits into two, resulting in two genetically identical individuals. Fraternal twins, on the other hand, occur when two separate eggs are fertilized by two different sperm cells, resulting in genetically unique individuals.

Explanation

Mitosis is the correct answer because it is a process of cell division in which a single cell divides into two identical daughter cells. During mitosis, the genetic material is replicated and distributed equally between the two daughter cells, resulting in genetically identical cells. This is similar to cloning where the offspring is genetically identical to the parent cell. Meiosis, on the other hand, is a type of cell division that produces cells with half the number of chromosomes, leading to genetic variation. Identical twins occur when a single fertilized egg splits into two, resulting in two genetically identical individuals. Fraternal twins, on the other hand, occur when two separate eggs are fertilized by two different sperm cells, resulting in genetically unique individuals.

18. Hemophilia is a sex-linked genetic disorder. Which statement best describes its inheritance pattern?

It is recessive in both males and females

It is recessive in males but dominant in females

It is recessive in females but dominant in males

It is dominant in both males and females

Hemophilia is a sex-linked genetic disorder, meaning it is carried on the X chromosome. The disorder is caused by a mutation in one of the genes responsible for blood clotting. Since males have only one X chromosome, if they inherit the mutated gene, they will develop hemophilia. Females, on the other hand, have two X chromosomes. In order for them to develop hemophilia, they would need to inherit the mutated gene on both X chromosomes. Therefore, hemophilia is recessive in both males and females.

Explanation

Hemophilia is a sex-linked genetic disorder, meaning it is carried on the X chromosome. The disorder is caused by a mutation in one of the genes responsible for blood clotting. Since males have only one X chromosome, if they inherit the mutated gene, they will develop hemophilia. Females, on the other hand, have two X chromosomes. In order for them to develop hemophilia, they would need to inherit the mutated gene on both X chromosomes. Therefore, hemophilia is recessive in both males and females.

19. Which of these statements is least likely to cause concern about genetically modified organisms?

Genetically modified organisms are responsible for an increase in allergies in young children

Genetically modified organisms will create resistant strains of bacteria that will be hard to control or get rid of.

Genetically modified organisms can be used to create substances that are harmful to humans and other organisms

Genetically modified organisms will create mutated genetic traits in the human population

The statement that genetically modified organisms will create mutated genetic traits in the human population is least likely to cause concern about genetically modified organisms because there is no evidence or scientific consensus to support this claim. While there may be concerns about the potential risks and impacts of genetically modified organisms, such as allergies, antibiotic resistance, and harmful substances, the idea that they will directly cause mutated genetic traits in humans is not supported by current research.

Explanation

The statement that genetically modified organisms will create mutated genetic traits in the human population is least likely to cause concern about genetically modified organisms because there is no evidence or scientific consensus to support this claim. While there may be concerns about the potential risks and impacts of genetically modified organisms, such as allergies, antibiotic resistance, and harmful substances, the idea that they will directly cause mutated genetic traits in humans is not supported by current research.