Multiple Choice Questions
Biology: Genetics and Biotechnology (Advanced)
Topic: Genetics and Biotechnology
Grade: 11
Question 1:
Which of the following is an example of a genotype?
a) Brown hair
b) Blue eyes
c) Tall height
d) Blood type A
Answer: d) Blood type A
Explanation: A genotype refers to the specific genetic makeup of an individual. Blood type A is determined by the presence of the A antigen on red blood cells, which is determined by the presence of the A allele in the genotype. This can be represented as AA or AO. In contrast, options a, b, and c are examples of phenotypes, which are the observable traits resulting from the interaction between an individual\’s genotype and the environment.
Question 2:
Which of the following accurately describes the process of transcription?
a) The synthesis of RNA from DNA template
b) The synthesis of DNA from RNA template
c) The replication of DNA
d) The translation of mRNA into protein
Answer: a) The synthesis of RNA from DNA template
Explanation: Transcription is the process by which an RNA molecule is synthesized using a DNA template. This process occurs in the nucleus of eukaryotic cells and is catalyzed by the enzyme RNA polymerase. The resulting RNA molecule is complementary to the DNA template strand and can serve as a template for translation, where mRNA is translated into protein.
Question 3:
A couple has two children with blood types A and O. What are the possible genotypes of the parents?
a) AA and AO
b) AO and BO
c) AB and O
d) BB and OO
Answer: a) AA and AO
Explanation: Blood type A is determined by the presence of the A antigen on red blood cells, which is determined by the presence of the A allele in the genotype. A person with blood type O does not have any antigens on their red blood cells and has the genotype OO. Since the couple has two children with blood types A and O, the parents must have genotypes AA and AO. When they reproduce, there is a 25% chance of producing a child with blood type O (OO) and a 75% chance of producing a child with blood type A (AA or AO).
Question 4:
Which of the following is an example of a sex-linked trait?
a) Eye color
b) Height
c) Hemophilia
d) Blood type
Answer: c) Hemophilia
Explanation: Hemophilia is a genetic disorder characterized by the inability of blood to clot properly. It is caused by mutations in genes located on the X chromosome. Since males only have one X chromosome, they are more likely to be affected by hemophilia if they inherit the mutated gene. In contrast, females have two X chromosomes and are less likely to be affected because they would need to inherit two mutated copies. Eye color, height, and blood type are not typically inherited in a sex-linked manner.
Question 5:
Which of the following techniques is used to cut DNA into specific fragments?
a) Polymerase chain reaction (PCR)
b) Gel electrophoresis
c) DNA sequencing
d) Restriction enzymes
Answer: d) Restriction enzymes
Explanation: Restriction enzymes, also known as restriction endonucleases, are enzymes that can recognize specific DNA sequences and cleave the DNA at those sites. These enzymes are often used in molecular biology techniques such as DNA cloning and genetic engineering. By cutting DNA into specific fragments, restriction enzymes allow for the isolation and manipulation of specific genes or regions of interest. PCR, gel electrophoresis, and DNA sequencing are other techniques used in molecular biology but do not involve cutting DNA.
Question 6:
Which of the following statements about genetic engineering is false?
a) It involves the manipulation of an organism\’s DNA
b) It can be used to produce genetically modified organisms (GMOs)
c) It has no potential risks or ethical concerns
d) It has applications in medicine, agriculture, and industry
Answer: c) It has no potential risks or ethical concerns
Explanation: Genetic engineering has great potential for various applications, but it also raises ethical concerns and potential risks. The manipulation of an organism\’s DNA can have unintended consequences, and the release of genetically modified organisms into the environment may have ecological impacts. There are also ethical considerations regarding the use of genetic engineering in humans, such as in gene therapy. Therefore, it is incorrect to state that genetic engineering has no potential risks or ethical concerns.
Question 7:
In a dihybrid cross between two individuals heterozygous for two traits, what is the phenotypic ratio of the offspring?
a) 1:1
b) 3:1
c) 9:3:3:1
d) 1:2:1
Answer: c) 9:3:3:1
Explanation: In a dihybrid cross, two individuals heterozygous for two traits are crossed. The phenotypic ratio of the offspring in this type of cross is 9:3:3:1, which means that for every 9 individuals with both dominant traits, there will be 3 individuals with the first dominant trait and the second recessive trait, 3 individuals with the first recessive trait and the second dominant trait, and 1 individual with both recessive traits. This ratio is a result of the independent assortment of alleles during gamete formation.
Question 8:
Which of the following is an example of a monogenic disorder?
a) Down syndrome
b) Cystic fibrosis
c) Huntington\’s disease
d) Sickle cell anemia
Answer: b) Cystic fibrosis
Explanation: A monogenic disorder is a genetic disorder caused by a mutation in a single gene. Cystic fibrosis is an example of a monogenic disorder caused by mutations in the CFTR gene. Down syndrome is a chromosomal disorder caused by the presence of an extra copy of chromosome 21. Huntington\’s disease is a neurodegenerative disorder caused by a mutation in the HTT gene. Sickle cell anemia is a genetic disorder caused by a mutation in the HBB gene.
Question 9:
Which of the following statements about DNA replication is true?
a) It occurs during the S phase of the cell cycle
b) It proceeds in the 5\’ to 3\’ direction
c) It is catalyzed by the enzyme DNA polymerase
d) It results in the formation of RNA molecules
Answer: a) It occurs during the S phase of the cell cycle
Explanation: DNA replication is the process by which a cell duplicates its DNA prior to cell division. It occurs during the S (synthesis) phase of the cell cycle. During replication, the DNA strands separate, and each strand serves as a template for the synthesis of a new complementary strand. This synthesis proceeds in the 5\’ to 3\’ direction and is catalyzed by the enzyme DNA polymerase. The result is two identical DNA molecules, each consisting of one original strand and one newly synthesized strand.
Question 10:
Which of the following organisms is an example of a genetically modified organism (GMO)?
a) A dog with a curly tail
b) A plant with increased resistance to pests
c) A cat with blue eyes
d) A bird with a longer wingspan
Answer: b) A plant with increased resistance to pests
Explanation: A genetically modified organism (GMO) is an organism whose genetic material has been altered using genetic engineering techniques. The purpose of genetic modification is often to introduce new traits or enhance existing traits. In this case, a plant with increased resistance to pests has been genetically modified to express genes that provide protection against pests. The other options (a dog with a curly tail, a cat with blue eyes, and a bird with a longer wingspan) do not involve genetic modification.
Question 11:
Which of the following statements about mutations is true?
a) Mutations always result in harmful effects
b) Mutations can occur spontaneously or be induced by mutagens
c) Mutations can only be inherited from one\’s parents
d) Mutations are always visible in an individual\’s phenotype
Answer: b) Mutations can occur spontaneously or be induced by mutagens
Explanation: Mutations are changes in the DNA sequence that can occur spontaneously or be induced by mutagens, which are agents that can cause DNA damage. Mutations can have various effects, including harmful, neutral, or beneficial effects. Not all mutations are visible in an individual\’s phenotype, especially if they occur in non-coding regions of the genome. Additionally, mutations can be inherited, but they can also occur de novo in an individual\’s somatic cells.
Question 12:
Which of the following is an example of a recombinant DNA technology?
a) Polymerase chain reaction (PCR)
b) DNA sequencing
c) Cloning a gene into a plasmid
d) Gel electrophoresis
Answer: c) Cloning a gene into a plasmid
Explanation: Recombinant DNA technology involves the manipulation of DNA molecules to create new combinations of genetic material. Cloning a gene into a plasmid is an example of recombinant DNA technology. In this process, a gene of interest is inserted into a plasmid, which can then be introduced into a host organism, such as bacteria, to produce multiple copies of the gene. PCR, DNA sequencing, and gel electrophoresis are other techniques used in molecular biology but do not involve the creation of new genetic combinations.
Question 13:
Which of the following techniques is used to determine the order of nucleotides in a DNA molecule?
a) Polymerase chain reaction (PCR)
b) Gel electrophoresis
c) DNA sequencing
d) Restriction enzymes
Answer: c) DNA sequencing
Explanation: DNA sequencing is a technique used to determine the order of nucleotides in a DNA molecule. There are several methods for DNA sequencing, including Sanger sequencing and next-generation sequencing. These methods involve the synthesis of DNA fragments using DNA polymerase and the incorporation of fluorescently labeled nucleotides. The resulting fragments are then separated and the sequence is determined based on the order of the labeled nucleotides. PCR, gel electrophoresis, and restriction enzymes are other techniques used in molecular biology but do not involve sequencing DNA.
Question 14:
Which of the following is an example of a polygenic trait?
a) Eye color
b) Blood type
c) Albinism
d) Height
Answer: d) Height
Explanation: A polygenic trait is a trait controlled by multiple genes, often with additive effects. Height is an example of a polygenic trait because it is influenced by the combined effects of multiple genes. Eye color is also influenced by multiple genes but is not typically considered a polygenic trait. Blood type is determined by a single gene with multiple alleles. Albinism is a genetic disorder caused by mutations in a single gene.
Question 15:
Which of the following is an example of a biotechnology product?
a) Insulin produced by genetically modified bacteria
b) A new antibiotic discovered from a natural source
c) A plant with increased drought tolerance obtained through selective breeding
d) A vaccine for a viral disease
Answer: a) Insulin produced by genetically modified bacteria
Explanation: Biotechnology products are products that are derived from or produced using living organisms or their components. Insulin produced by genetically modified bacteria is an example of a biotechnology product. The bacteria are genetically modified to produce human insulin, which can then be harvested and used to treat diabetes. The other options (a new antibiotic, a plant with increased drought tolerance, and a vaccine) are also related to biotechnology, but they do not involve the direct use of genetically modified organisms.