BS 161 Final Exam (New Info) UPDATED
ACTUAL Questions and CORRECT
Answers
What is the first thing to occur in DNA replication?
the strands of the DNA double helix are separated
the extension of DNA from the 3′ end of the RNA primer
the synthesis of a short RNA primer
the removal of the RNA primer, which is replaced by DNA - CORRECT ANSWER -a
On which strand are new nucleotides being added in the same direction as the replication fork is
opening?
the lagging strand
On both strands, DNA synthesis is proceeding in the same direction as the replication fork
the leading strand - CORRECT ANSWER -c
On which strand is DNA synthesis discontinuous, occurring in fragments that are later
connected?
the leading strand
,the lagging strand
Both strands synthesize DNA in fragments. - CORRECT ANSWER -b
Which statement about DNA replication is true?
When DNA polymerase reaches a primer from prior DNA synthesis, the primer is removed and
replaced with DNA
The lagging strand requires an RNA primer to initiate DNA synthesis, whereas the leading strand
does not require an RNA primer
On the leading strand, new DNA is added to the 3′ end of the growing strand, whereas on the
lagging strand, new DNA is added to the 5′ end
DNA polymerase performs DNA synthesis on the leading strand, and RNA polymerase performs
synthesis on the lagging strand. - CORRECT ANSWER -a
RNA primase lays down an RNA primer to start DNA replication. If a mutation occurs that
blocks the function of RNA primase, which synthesis of which strand is affected, and why?
The leading strand is affected because it leads DNA synthesis.
The lagging strand is affected because it requires an RNA primer for each Okazaki fragment
produced.
Both strands are affected because all DNA polymerase can only add new nucleotides to a 3′-OH
present at the end of the RNA primer. - CORRECT ANSWER -c
,Each DNA parent strand within a replication bubble acts as a template strand that produces:
only lagging strands.
two leading strands or two lagging strands.
one leading strand and one lagging strand.
either a leading strand or a lagging strand.
only leading strands. - CORRECT ANSWER -c
Telomerase is fully active in _____ and _____ cells, but almost completely inactive in _____
cells.
germ; stem; somatic
stem; blood; germ
somatic; blood; germ
germ; somatic; stem
somatic; germ; stem - CORRECT ANSWER -a
Synthesis of nucleic acids always occurs in the 5′ → 3′ direction.
true
, false - CORRECT ANSWER -a
What is the name of the enzyme that separates the two strands of DNA during replication?
topoisomerase
DNA ligase
DNA polymerase
primase
helicase - CORRECT ANSWER -e
What is the function of the enzyme DNA polymerase?
to synthesize a strand of DNA using a polypeptide as a template
to synthesize a strand of DNA using DNA as a template
to synthesize a strand of mRNA using mRNA as a template
to synthesize a polypeptide using DNA as a template
to synthesize a strand of mRNA using DNA as a template - CORRECT ANSWER -b
Which of the statements about the strands of a newly replicated DNA molecule is correct?
ACTUAL Questions and CORRECT
Answers
What is the first thing to occur in DNA replication?
the strands of the DNA double helix are separated
the extension of DNA from the 3′ end of the RNA primer
the synthesis of a short RNA primer
the removal of the RNA primer, which is replaced by DNA - CORRECT ANSWER -a
On which strand are new nucleotides being added in the same direction as the replication fork is
opening?
the lagging strand
On both strands, DNA synthesis is proceeding in the same direction as the replication fork
the leading strand - CORRECT ANSWER -c
On which strand is DNA synthesis discontinuous, occurring in fragments that are later
connected?
the leading strand
,the lagging strand
Both strands synthesize DNA in fragments. - CORRECT ANSWER -b
Which statement about DNA replication is true?
When DNA polymerase reaches a primer from prior DNA synthesis, the primer is removed and
replaced with DNA
The lagging strand requires an RNA primer to initiate DNA synthesis, whereas the leading strand
does not require an RNA primer
On the leading strand, new DNA is added to the 3′ end of the growing strand, whereas on the
lagging strand, new DNA is added to the 5′ end
DNA polymerase performs DNA synthesis on the leading strand, and RNA polymerase performs
synthesis on the lagging strand. - CORRECT ANSWER -a
RNA primase lays down an RNA primer to start DNA replication. If a mutation occurs that
blocks the function of RNA primase, which synthesis of which strand is affected, and why?
The leading strand is affected because it leads DNA synthesis.
The lagging strand is affected because it requires an RNA primer for each Okazaki fragment
produced.
Both strands are affected because all DNA polymerase can only add new nucleotides to a 3′-OH
present at the end of the RNA primer. - CORRECT ANSWER -c
,Each DNA parent strand within a replication bubble acts as a template strand that produces:
only lagging strands.
two leading strands or two lagging strands.
one leading strand and one lagging strand.
either a leading strand or a lagging strand.
only leading strands. - CORRECT ANSWER -c
Telomerase is fully active in _____ and _____ cells, but almost completely inactive in _____
cells.
germ; stem; somatic
stem; blood; germ
somatic; blood; germ
germ; somatic; stem
somatic; germ; stem - CORRECT ANSWER -a
Synthesis of nucleic acids always occurs in the 5′ → 3′ direction.
true
, false - CORRECT ANSWER -a
What is the name of the enzyme that separates the two strands of DNA during replication?
topoisomerase
DNA ligase
DNA polymerase
primase
helicase - CORRECT ANSWER -e
What is the function of the enzyme DNA polymerase?
to synthesize a strand of DNA using a polypeptide as a template
to synthesize a strand of DNA using DNA as a template
to synthesize a strand of mRNA using mRNA as a template
to synthesize a polypeptide using DNA as a template
to synthesize a strand of mRNA using DNA as a template - CORRECT ANSWER -b
Which of the statements about the strands of a newly replicated DNA molecule is correct?
