BIO 340 Final Exam/Questions & verified Ans/ A+
Score Solution/
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
, 2
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
, 3
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
, 4
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