MCB 3023 Exam 2 Questions with Verified Solutions Latest 2025
Term for a special sequence at the end of the chromosome in eukaryal cells - Answers A
telomere
Replication of the bacterial chromosome begins at how many locations? - Answers One
In bacterial cells mRNA can be polycistronic. What does this mean? - Answers It contains the
code for multiple peptides
What did the experiment by Fred Griffinith in 1928 with the R and S strains of Streptococcus
pneumoniae demonstrate? - Answers Genetic material from one strain could be transferred to
another strain
Which of these would a signal peptide be used for in bacteria? - Answers To move a protein to
the outside of the cell
What does Rho-independent termination of transcription in bacteria involve? - Answers The
formation of a hairpin loop followed by a poly U sequence
Which statement below is FALSE regarding replication of the bacterial chromosome - Answers
The leading strand is replicated in the 5' to 3' direction and the lagging strand in the 3' to 5'
direction
A bacterium which cannot synthesize all organic molecules needed for its growth from a single
organic carbon source (e.g. glucose) is known as a/an: - Answers Auxotroph
Genetic elements that are able to "jump" around on the chromosome - Answers Transposons
A vector with a genome consisting of the cos site derived from phage lambda flanked by
approximately 35 to 45 kb exogenous DNA would be known as a: - Answers Cosmid vector
Which of these enzymes is not required for homologous recombination to occur? - Answers
DNA polymerase
What is an organism's complete collection of alleles called? - Answers Genotype
DNA microarray analysis may be used to study: - Answers Gene expression in cells grown under
different conditions
You are receiving a bacterial strain from the American Type and Culture Collection. The strain is
labeled E. coli K12 Leu- Pro-. What does this mean? - Answers The strain is a mutant incapable
of leucine and proline synthesis
You are analyzing a ~20,000 bp long DNA fragment that is part of a metagenome. Based on
your experience in identifying microorganisms, what gene would you look for to best identify the
organism that the DNA fragment might have come from? - Answers 16S rRNA gene
, Suppose it is observed that a small section of a microorganism's chromosome varies
significantly in GC content from the majority of the chromosome. What likely caused this? -
Answers Horizontal gene transfer
Which of these is another term for the Sanger method of DNA sequencing? - Answers Dideoxy
sequencing
Term for genes from different organisms that encode for proteins that carry out the same
function but have different sequences. - Answers Orthologs
What are micro RNAs? - Answers small regulatory RNAs
After the translational process the polypeptide folds into the appropriate conformation for
proper functioning. What group of proteins aids in protein folding? - Answers chaperonins
The Hershey and Chase experiment was able to conclusively demonstrate that DNA, not protein,
was the genetic material. They were able to distinguish DNA from protein since labeled _____
incorporated into DNA while labeled _____ incorporated into proteins. - Answers phosphorous;
sulfur
Suppose a microbe has died and lysed, exposing its DNA to the environment. Some of this DNA
was taken up by another unrelated microbe and incorporated into its genome. This is an
example of which process? - Answers horizontal gene transfer
Escherichia coli strain K12 is considered a wild-type strain and does not have any nutritional
vitamin requirements. What term applies to this strain? - Answers Prototroph
What is considered a bacterial strain's genome: - Answers chromosome, plasmids, and
lysogenic phage DNA
Term for the direct transfer of DNA from a living donor bacterium to a recipient bacterium. -
Answers conjugation
The ________ protein is important in the process of recombination. - Answers RecA
The Sanger method of sequencing uses ALL of the following EXCEPT: - Answers restriction
enzymes
Genes which confer invasiveness to a pathogen and whose GC content varies significantly from
that of the total genome constitute: - Answers Pathogenicity islands
DNA and RNA are both used in every living cell. What makes them different? - Answers All
statements are true
In Bacteria the replication of the chromosome is initiated by binding of which protein to the
origin of replication? - Answers DnaA
Term for a special sequence at the end of the chromosome in eukaryal cells - Answers A
telomere
Replication of the bacterial chromosome begins at how many locations? - Answers One
In bacterial cells mRNA can be polycistronic. What does this mean? - Answers It contains the
code for multiple peptides
What did the experiment by Fred Griffinith in 1928 with the R and S strains of Streptococcus
pneumoniae demonstrate? - Answers Genetic material from one strain could be transferred to
another strain
Which of these would a signal peptide be used for in bacteria? - Answers To move a protein to
the outside of the cell
What does Rho-independent termination of transcription in bacteria involve? - Answers The
formation of a hairpin loop followed by a poly U sequence
Which statement below is FALSE regarding replication of the bacterial chromosome - Answers
The leading strand is replicated in the 5' to 3' direction and the lagging strand in the 3' to 5'
direction
A bacterium which cannot synthesize all organic molecules needed for its growth from a single
organic carbon source (e.g. glucose) is known as a/an: - Answers Auxotroph
Genetic elements that are able to "jump" around on the chromosome - Answers Transposons
A vector with a genome consisting of the cos site derived from phage lambda flanked by
approximately 35 to 45 kb exogenous DNA would be known as a: - Answers Cosmid vector
Which of these enzymes is not required for homologous recombination to occur? - Answers
DNA polymerase
What is an organism's complete collection of alleles called? - Answers Genotype
DNA microarray analysis may be used to study: - Answers Gene expression in cells grown under
different conditions
You are receiving a bacterial strain from the American Type and Culture Collection. The strain is
labeled E. coli K12 Leu- Pro-. What does this mean? - Answers The strain is a mutant incapable
of leucine and proline synthesis
You are analyzing a ~20,000 bp long DNA fragment that is part of a metagenome. Based on
your experience in identifying microorganisms, what gene would you look for to best identify the
organism that the DNA fragment might have come from? - Answers 16S rRNA gene
, Suppose it is observed that a small section of a microorganism's chromosome varies
significantly in GC content from the majority of the chromosome. What likely caused this? -
Answers Horizontal gene transfer
Which of these is another term for the Sanger method of DNA sequencing? - Answers Dideoxy
sequencing
Term for genes from different organisms that encode for proteins that carry out the same
function but have different sequences. - Answers Orthologs
What are micro RNAs? - Answers small regulatory RNAs
After the translational process the polypeptide folds into the appropriate conformation for
proper functioning. What group of proteins aids in protein folding? - Answers chaperonins
The Hershey and Chase experiment was able to conclusively demonstrate that DNA, not protein,
was the genetic material. They were able to distinguish DNA from protein since labeled _____
incorporated into DNA while labeled _____ incorporated into proteins. - Answers phosphorous;
sulfur
Suppose a microbe has died and lysed, exposing its DNA to the environment. Some of this DNA
was taken up by another unrelated microbe and incorporated into its genome. This is an
example of which process? - Answers horizontal gene transfer
Escherichia coli strain K12 is considered a wild-type strain and does not have any nutritional
vitamin requirements. What term applies to this strain? - Answers Prototroph
What is considered a bacterial strain's genome: - Answers chromosome, plasmids, and
lysogenic phage DNA
Term for the direct transfer of DNA from a living donor bacterium to a recipient bacterium. -
Answers conjugation
The ________ protein is important in the process of recombination. - Answers RecA
The Sanger method of sequencing uses ALL of the following EXCEPT: - Answers restriction
enzymes
Genes which confer invasiveness to a pathogen and whose GC content varies significantly from
that of the total genome constitute: - Answers Pathogenicity islands
DNA and RNA are both used in every living cell. What makes them different? - Answers All
statements are true
In Bacteria the replication of the chromosome is initiated by binding of which protein to the
origin of replication? - Answers DnaA
