UCI Biology 93 Midterm #2 DNA Replication
Lectures 10-11 questions with accurate answers
A new strand can elongate only in the __' to __' direction Ans✓✓✓ 5' --
> 3'
Can damage of the DNA occur after replication? Ans✓✓✓ yes
DNA is a polymer of ___________ Ans✓✓✓ nucleotides
DNA polymerases add nucleotides only on the __' end of a growing
DNA strand Ans✓✓✓ 3'
Explain how the lagging strand must be primed separately Ans✓✓✓ 1.
The strand is primed, with RNA nucleotides
2. DNA pol I replaces RNA nucleotides with DNA nucleotides
3. DNA ligase joins the sugar-phosphate backbones of the Okazaki
fragments into a continuous strand
How do the many replication bubbles that form in eukaryotic
chromosomes help with the replication? Ans✓✓✓ the process is much
faster
How does DNA polymerases catalyze the synthesis of new DNA
Ans✓✓✓ adds nucleotides to a preexisting chain
, How does DNA polymerases participate in the proofreading and
repairing of DNA? Ans✓✓✓ It proofreads each nucleotide against its
template as soon as it is covalently bonded to the growing strand
How does nuclease participate in proofreading and repairing DNA?
Ans✓✓✓ cuts the damaged segment of the strand and the gap is then
filled in with nucleotides
How is the lagging strand synthesized? Ans✓✓✓ As a series of
Okazaki fragments
Identify the purines and the number of of rings Ans✓✓✓ Adenine and
Guanine, 2
Identify the pyrimidines and the number of rings Ans✓✓✓ Cytosine
and Thymines, 1
In what direction does the lagging strand work? Ans✓✓✓ away from
the replication fork
What alleviates the tight stressing of the untwisting double helix
structure of DNA? How? Ans✓✓✓ topoisomerase; breaks, swivels, and
rejoins DNA strands
What are Chargaff's rules? Ans✓✓✓ 1. the base composition v of DNA
aries between species
Lectures 10-11 questions with accurate answers
A new strand can elongate only in the __' to __' direction Ans✓✓✓ 5' --
> 3'
Can damage of the DNA occur after replication? Ans✓✓✓ yes
DNA is a polymer of ___________ Ans✓✓✓ nucleotides
DNA polymerases add nucleotides only on the __' end of a growing
DNA strand Ans✓✓✓ 3'
Explain how the lagging strand must be primed separately Ans✓✓✓ 1.
The strand is primed, with RNA nucleotides
2. DNA pol I replaces RNA nucleotides with DNA nucleotides
3. DNA ligase joins the sugar-phosphate backbones of the Okazaki
fragments into a continuous strand
How do the many replication bubbles that form in eukaryotic
chromosomes help with the replication? Ans✓✓✓ the process is much
faster
How does DNA polymerases catalyze the synthesis of new DNA
Ans✓✓✓ adds nucleotides to a preexisting chain
, How does DNA polymerases participate in the proofreading and
repairing of DNA? Ans✓✓✓ It proofreads each nucleotide against its
template as soon as it is covalently bonded to the growing strand
How does nuclease participate in proofreading and repairing DNA?
Ans✓✓✓ cuts the damaged segment of the strand and the gap is then
filled in with nucleotides
How is the lagging strand synthesized? Ans✓✓✓ As a series of
Okazaki fragments
Identify the purines and the number of of rings Ans✓✓✓ Adenine and
Guanine, 2
Identify the pyrimidines and the number of rings Ans✓✓✓ Cytosine
and Thymines, 1
In what direction does the lagging strand work? Ans✓✓✓ away from
the replication fork
What alleviates the tight stressing of the untwisting double helix
structure of DNA? How? Ans✓✓✓ topoisomerase; breaks, swivels, and
rejoins DNA strands
What are Chargaff's rules? Ans✓✓✓ 1. the base composition v of DNA
aries between species
