10 Jun Eukaryotic DNA replication initiates replication at multiple origins
Question
22. Eukaryotic DNA replication initiates replication at multiple origins of replication simultaneously. How is eukaryotic replication initiated to ensure simultaneous initiation at multiple origins?
a) A Pre-replication complex (preRC) is formed at all hemimethylated origins.
b) The Pre-replication complex (preRC) forms in Go phase.
c) Cyclin-dependent protein kinase (CDK) enzymes are active during formation of PreReplication Complex (preRC).
d) Cyclin-dependent protein kinase (CDK) enzymes activate the Pre-RC to allow for coordinated activation of replication once other replication factors associate to form the Replication Complex (RC).
e) None of these answers is correct.
22. What are the major differences between helicases, topoisomerases, and ligases used in DNA replication?
a) Helicases and topoisomerases unwind DNA, with helicases functioning to relieve supercoil stress ahead of the replication process; and ligases seal DNA that has been broken or synthesized as Okazaki fragments.
b) All three unwind DNA, but helicases do so before the replication machinery, ligases with the machinery, and topoisomerases ahead of it.
c) Helicases and topoisomerases unwind DNA, with topoisomerases functioning to relieve supercoil stress ahead of the replication fork; and ligases seal DNA that has been broken or synthesized as Okazaki fragments.
d) Helicases and topoisomerases bind double-stranded DNA, and ligases bind RNA-DNA hybrids.
e) None of the above.
31 .Which of the following is FALSE about Okazaki fragments?
a) Okazaki fragments are formed during replication of the lagging strand.
b) Each Okazaki fragment is primed at the 5′ end by a short RNA of 10-13 nucleotides
c) The RNA primer of the Okazaki fragment is removed by nuclease action and replaced with DNA nucleotides.
d) Okazaki fragments are joined by ligase after the replication fork has passed.
e) Okazaki fragments are generated by continuous synthesis on the leading strand.
32. You have just performed an experiment using the DNA pol Ill core and clamp proteins, and 3 different single-stranded circular plasmids (A, B, and C) with RNA primer hybridized to each of them. After incubation of these components with dNTPs (some of which were radioactively-labeled), separation of the reaction products on an agarose gel, and then exposure to autoradiography, you observe the following banding pattern.
Which of the following best explains this result:
a) Plasmid ‘C’ was initially bound by the DNA pol Ill core and a clamp proteins.
b) Plasmid ‘A’ shows less radioactive signal than ‘B’ and ‘C’ because it is the biggest plasmid and therefore incorporates a lower proportion of radioactive dNMPs compared to nonradioactive dNMPs.
c) Plasmid ‘B’ has numerous origins of replication.
d) Plasmids ‘A’ and ‘B’ both have clamp proteins bound to them.
e) Plasmid ‘C’ has a ß clamp protein, but plasmid ‘A’ does not.
Time(s) 15 30 60 90
Our website has a team of professional writers who can help you write any of your homework. They will write your papers from scratch. We also have a team of editors just to make sure all papers are of HIGH QUALITY & PLAGIARISM FREE. To make an Order you only need to click Ask A Question and we will direct you to our Order Page at WriteDemy. Then fill Our Order Form with all your assignment instructions. Select your deadline and pay for your paper. You will get it few hours before your set deadline.
Fill in all the assignment paper details that are required in the order form with the standard information being the page count, deadline, academic level and type of paper. It is advisable to have this information at hand so that you can quickly fill in the necessary information needed in the form for the essay writer to be immediately assigned to your writing project. Make payment for the custom essay order to enable us to assign a suitable writer to your order. Payments are made through Paypal on a secured billing page. Finally, sit back and relax.
About Writedemy
We are a professional paper writing website. If you have searched a question and bumped into our website just know you are in the right place to get help in your coursework. We offer HIGH QUALITY & PLAGIARISM FREE Papers.
How It Works
To make an Order you only need to click on “Order Now” and we will direct you to our Order Page. Fill Our Order Form with all your assignment instructions. Select your deadline and pay for your paper. You will get it few hours before your set deadline.
Are there Discounts?
All new clients are eligible for 20% off in their first Order. Our payment method is safe and secure.