Bacterial Genetics sample questions

Question: What characteristics make bacteria like E. coli attractive as model organisms?

Answer Options:
• A) Short generation time, simple genome relative to that of humans, easily mutagenized, haploid, gene control mechanisms identical to eukaryotes
• B) Short generation time, simple genome relative to that of humans, easily mutagenized, haploid
• C) Short generation time, genome as complex as that of humans, easily mutagenized, haploid
• D) Short generation time, simple genome relative to that of humans, easily mutagenized, diploid

Answer: B) Short generation time, simple genome relative to that of humans, easily mutagenized, haploid

Question: Two F+ E. coli strains are co-cultured in the same flask. One is Str^r Thr+ and the other is Gen^r Thr−. The culture is then plated on minimal media that is supplemented with gentamycin only (not threonine) and a few colonies grow. What sort of genetic exchange is most likely occurring?

Answer Options:
• A) Transformation
• B) Conjugation
• C) Transduction
• D) Electroporation

Answer: B) Conjugation

Question: Which technique would most likely be used for mapping genes that are separated by 2 × 10⁵ base pairs?

Answer Options:
• A) Specialized transduction
• B) Generalized transduction
• C) Conjugation
• D) Transformation

Answer: C) Conjugation

Question: In an Hfr strain, the F episome is integrated between genes A and B. When this Hfr mates with an F− strain, gene B is always transferred first to the F− cell. What is the last bacterial gene that could possibly (at least in theory) be transferred to the F− from the host chromosome?

Answer Options:
• A) A gene that is 90 minutes from gene A
• B) A gene that is at 30 minutes from gene A
• C) Gene A
• D) A gene that is at 60 minutes from gene A

Answer: A) A gene that is 90 minutes from gene A

Question: If an organism is isolated that has no nuclear membrane and the DNA is condensed into a body in the cytoplasm, this organism would most likely be classified as

Answer Options:
• A) A prokaryote.
• B) A eukaryote.
• C) A pathogen.
• D) Either a eukaryote or prokaryote.

Answer: A) A prokaryote

Question: What would you anticipate would be true about the metabolism of a bacterial species isolated from water samples, one at the surface and another from a hot vent on the ocean floor?

Answer Options:
• A) The species from the water surface would be more likely to be able to conduct photosynthesis.
• B) The species from the hot vent would be more likely to be able to conduct photosynthesis.
• C) The species from the hot vent would be more likely to be able to fix nitrogen.
• D) The species from the hot vent would be more likely to be able to degrade oil.

Answer: A) The species from the water surface would be more likely to be able to conduct photosynthesis.

Question: What is a property of a pathogenic bacterium?

Answer Options:
• A) It may produce a protein that interferes with basic cellular functions.
• B) All strains of the same species are also pathogenic.
• C) It probably conducts photosynthesis.
• D) It is resistant to all antibiotics.

Answer: A) It may produce a protein that interferes with basic cellular functions.

Question: Which gene would you predict would be most likely to be part of a core genome and not the pangenome?

Answer Options:
• A) Gene encoding DNA polymerase
• B) Gene conferring antibiotic resistance
• C) Gene conferring metal resistance
• D) Gene encoding an enzyme required for lactose utilization

Answer: A) Gene encoding DNA polymerase

Question: What is a difference between a Tn and IS element?

Answer Options:
• A) Tn elements can carry antibiotic resistance genes.
• B) IS elements carry a transposase gene.
• C) Tn elements integrate into plasmids and genomes.
• D) IS elements integrate into plasmids and genomes.

Answer: A) Tn elements can carry antibiotic resistance genes.

Question: Metagenomics may be useful because

Answer Options:
• A) It could be used to detect or predict human diseases.
• B) It is a technique for sequencing a bacterial genome rapidly.
• C) Metagenomes do not change rapidly.
• D) Metagenomes are not responsive to environmental changes.

Answer: A) It could be used to detect or predict human diseases.

Bacterial Genetics sample questions

Question: What characteristics make bacteria like E. coli attractive as model organisms?

Question: Two F+ E. coli strains are co-cultured in the same flask. One is Strr Thr+ and the other is Genr Thr−. The culture is then plated on minimal media that is supplemented with gentamycin only (not threonine) and a few colonies grow. What sort of genetic exchange is most likely occurring?

Question: Which technique would most likely be used for mapping genes that are separated by 2 × 105 base pairs?

Question: In an Hfr strain, the F episome is integrated between genes A and B. When this Hfr mates with an F− strain, gene B is always transferred first to the F− cell. What is the last bacterial gene that could possibly (at least in theory) be transferred to the F− from the host chromosome?

Question: If an organism is isolated that has no nuclear membrane and the DNA is condensed into a body in the cytoplasm, this organism would most likely be classified as

Question: What would you anticipate would be true about the metabolism of a bacterial species isolated from water samples, one at the surface and another from a hot vent on the ocean floor?

Question: What is a property of a pathogenic bacterium?

Question: Which gene would you predict would be most likely to be part of a core genome and not the pangenome?

Question: What is a difference between a Tn and IS element?

Question: Metagenomics may be useful because

Question: Two F+ E. coli strains are co-cultured in the same flask. One is Str^r Thr+ and the other is Gen^r Thr−. The culture is then plated on minimal media that is supplemented with gentamycin only (not threonine) and a few colonies grow. What sort of genetic exchange is most likely occurring?

Question: Which technique would most likely be used for mapping genes that are separated by 2 × 10⁵ base pairs?