BIO 340 Final Exam|| Questions and Complete Answers
|| 2025 Edition, || RATED A+
What type of bonds are formed between complementary DNA bases? - ANSWER Hydrogen
Bonds
Which of the following forms the backbone of a polynucleotide chain? - ANSWER alternating
sugar and phosphate groups
Guanine and adenine are purines found in DNA - ANSWER true
What fraction of the nucleotides in a doubles-stranded DNA molecule are cytosine and
thymine? - ANSWER 50%
What is one difference between DNA replication in bacteria versus eukaryotes? - ANSWER
Eukaryotic chromosomes have many origins of replication, while bacteria have only one origin
of replication
What is the maximum rate between DNA replication in E. coli - ANSWER 1000 nucleotides
During DNA replication in E. coli, what is the role of DnaA? - ANSWER DnaA bends DNA,
hydrolyzing the hydrogen bonds in the 13-mer region of otic and creating an open complex
Which of the following statements about DNA replication is true? - ANSWER Single-strand
binding proteins stabilize the open conformation of the unwound DNA
Which of the following reagents is not required for the polymerase chain reaction? - ANSWER
Dideoxynucleotide triphosphate
,Which of the following would you find in a Sanger sequencing reaction but not in a polymerase
chain reaction? - ANSWER ddNTPs
Which of the following statements about ddNTPs is true? - ANSWER they have a hydrogen at
the 3' carbon of the sugar
The principles of complementary base pairing and antiparallel polarity of nucleic acid strands is
a duplex are universal for the formation of nucleic acid duplexes. What is the chemical basis for
this university? - ANSWER
You wish to create a mutation in which you prevent access of RNA polymerase to the gene.
Which region of a gene would you target? - ANSWER promoter sequence
Which region(s) of a gene are not found within the mRNA transcript? - ANSWER promoter
region
Which of the following statements regarding Nucleotide Excision repair (NER) and Base Excision
Repair (BER) is true? - ANSWER both NER and BER involve the removal of one or more damaged
bases by a nuclease
How large is an origin of replication of E. coli? - ANSWER 245 base pairs
Which of the following enzymatic activities is NOT involved in DNA replication - ANSWER RNA-
dependent DNA polymerase
Which activity of DNA polymerase is responsible for its ability to proofread newly synthesized
DNA - ANSWER 3'>5' exonuclease which cleaves mismatched nucleotides
,How many mutations would you expect to see in the human genome (6x10^9) if mismatches
could not be repaired? - ANSWER 6x10^9/10^4= 600,000 mutations
What would the consequences be of having DNA polymerase with out 5' -> 3' exonuclease
activity? - ANSWER the RNA primer will stay
What is the correct order of enzyme action during DNA replication? - ANSWER
helices/topoisomerase activity, priming, DNA polymerization/proofreading, 5'-3' exonuclease
activity/DNA polymerization, ligation
Why is telomerase important? - ANSWER It is important for extension
You isolate a mutant of this gene that encodes the following protein:
N-Met-Gln-Cys-Lys-Ser-C
What mutation can give you this mutant protein - ANSWER Deletion of a C
Which of the following statements are FALSE? - ANSWER the Trp Operon is under positive
control
*LAC has both positive and negative regulation* - ANSWER
Trp is negative controlled - ANSWER
Under which of the following conditions will E. coli make large amounts of B- galactosidase? -
ANSWER I+O+Z+, glucose absent, lactose present
I-OcZ+, glucose absent, lactose absent
, Under what condition will E. coli make the least amount of B-galactosidase? - ANSWER IsO+Z+,
glucose absent, lactose present
For the lac operon gene regulation system, which of the following is false? - ANSWER in the
presence of low levels of glucose and lactose, even with mutation happening on the operator
(operator cannot bind to repressor), there are still no transcription of lac genes
The expression of a gene can be increase by? - ANSWER knocking out its repressor
In the Trp operon of E. coli, the Trytophan repressor protein, Trp R, will bind to the operator to
prevent transcription only in the presence of tryptophan. What is tryptophan an example of? -
ANSWER Co-repressor
Which of the following is required for transcription - ANSWER RNA polymerase
Which of the following nucleosomes modifications will lead to closed promoters - ANSWER De-
acetylation
All of the following codons/anticodons are associated with the amino acid Leucine. Which of the
following anti-codon/codon pairs is an example of wobble paring - ANSWER Anticodon: 5' UAA
3' paired with codon
5' UUA 3' or 5' UUG 3'
Why are mitochondria and plastid genomes highly reduced compared to their free living
relatives (Ammar) - ANSWER Gene loss and Endosymbiotic Gene Transfer
Where are most Mitochondrial genes encoded? - ANSWER Nucleus
|| 2025 Edition, || RATED A+
What type of bonds are formed between complementary DNA bases? - ANSWER Hydrogen
Bonds
Which of the following forms the backbone of a polynucleotide chain? - ANSWER alternating
sugar and phosphate groups
Guanine and adenine are purines found in DNA - ANSWER true
What fraction of the nucleotides in a doubles-stranded DNA molecule are cytosine and
thymine? - ANSWER 50%
What is one difference between DNA replication in bacteria versus eukaryotes? - ANSWER
Eukaryotic chromosomes have many origins of replication, while bacteria have only one origin
of replication
What is the maximum rate between DNA replication in E. coli - ANSWER 1000 nucleotides
During DNA replication in E. coli, what is the role of DnaA? - ANSWER DnaA bends DNA,
hydrolyzing the hydrogen bonds in the 13-mer region of otic and creating an open complex
Which of the following statements about DNA replication is true? - ANSWER Single-strand
binding proteins stabilize the open conformation of the unwound DNA
Which of the following reagents is not required for the polymerase chain reaction? - ANSWER
Dideoxynucleotide triphosphate
,Which of the following would you find in a Sanger sequencing reaction but not in a polymerase
chain reaction? - ANSWER ddNTPs
Which of the following statements about ddNTPs is true? - ANSWER they have a hydrogen at
the 3' carbon of the sugar
The principles of complementary base pairing and antiparallel polarity of nucleic acid strands is
a duplex are universal for the formation of nucleic acid duplexes. What is the chemical basis for
this university? - ANSWER
You wish to create a mutation in which you prevent access of RNA polymerase to the gene.
Which region of a gene would you target? - ANSWER promoter sequence
Which region(s) of a gene are not found within the mRNA transcript? - ANSWER promoter
region
Which of the following statements regarding Nucleotide Excision repair (NER) and Base Excision
Repair (BER) is true? - ANSWER both NER and BER involve the removal of one or more damaged
bases by a nuclease
How large is an origin of replication of E. coli? - ANSWER 245 base pairs
Which of the following enzymatic activities is NOT involved in DNA replication - ANSWER RNA-
dependent DNA polymerase
Which activity of DNA polymerase is responsible for its ability to proofread newly synthesized
DNA - ANSWER 3'>5' exonuclease which cleaves mismatched nucleotides
,How many mutations would you expect to see in the human genome (6x10^9) if mismatches
could not be repaired? - ANSWER 6x10^9/10^4= 600,000 mutations
What would the consequences be of having DNA polymerase with out 5' -> 3' exonuclease
activity? - ANSWER the RNA primer will stay
What is the correct order of enzyme action during DNA replication? - ANSWER
helices/topoisomerase activity, priming, DNA polymerization/proofreading, 5'-3' exonuclease
activity/DNA polymerization, ligation
Why is telomerase important? - ANSWER It is important for extension
You isolate a mutant of this gene that encodes the following protein:
N-Met-Gln-Cys-Lys-Ser-C
What mutation can give you this mutant protein - ANSWER Deletion of a C
Which of the following statements are FALSE? - ANSWER the Trp Operon is under positive
control
*LAC has both positive and negative regulation* - ANSWER
Trp is negative controlled - ANSWER
Under which of the following conditions will E. coli make large amounts of B- galactosidase? -
ANSWER I+O+Z+, glucose absent, lactose present
I-OcZ+, glucose absent, lactose absent
, Under what condition will E. coli make the least amount of B-galactosidase? - ANSWER IsO+Z+,
glucose absent, lactose present
For the lac operon gene regulation system, which of the following is false? - ANSWER in the
presence of low levels of glucose and lactose, even with mutation happening on the operator
(operator cannot bind to repressor), there are still no transcription of lac genes
The expression of a gene can be increase by? - ANSWER knocking out its repressor
In the Trp operon of E. coli, the Trytophan repressor protein, Trp R, will bind to the operator to
prevent transcription only in the presence of tryptophan. What is tryptophan an example of? -
ANSWER Co-repressor
Which of the following is required for transcription - ANSWER RNA polymerase
Which of the following nucleosomes modifications will lead to closed promoters - ANSWER De-
acetylation
All of the following codons/anticodons are associated with the amino acid Leucine. Which of the
following anti-codon/codon pairs is an example of wobble paring - ANSWER Anticodon: 5' UAA
3' paired with codon
5' UUA 3' or 5' UUG 3'
Why are mitochondria and plastid genomes highly reduced compared to their free living
relatives (Ammar) - ANSWER Gene loss and Endosymbiotic Gene Transfer
Where are most Mitochondrial genes encoded? - ANSWER Nucleus
