DNA Replication Mechanisms Quiz

<p>It detaches from the lagging strand template. (A)</p> Signup and view all the answers

<p>It creates multiple RNA primers in a discontinuous fashion. (B)</p> Signup and view all the answers

<p>Semi-conservative replication (D)</p> Signup and view all the answers

<p>S Phase (C)</p> Signup and view all the answers

<p>Replication fork (B)</p> Signup and view all the answers

<p>10,000-100,000 (B)</p> Signup and view all the answers

<p>Replicons (B)</p> Signup and view all the answers

<p>DNA Polymerase III (A)</p> Signup and view all the answers

<p>10-100 (A)</p> Signup and view all the answers

<p>RNA polymerase (D)</p> Signup and view all the answers

<p>To concentrate multiple replicons for simultaneous replication (A)</p> Signup and view all the answers

<p>Hydrogen bond breaking (B)</p> Signup and view all the answers

<p>It covalently joins 3’ dNT to 5’ end of Okazaki fragments. (D)</p> Signup and view all the answers

<p>Human cells have 10,000-100,000 different origins of replication. (A)</p> Signup and view all the answers

<p>Replication machinery displaces them but they quickly reassemble. (B)</p> Signup and view all the answers

<p>To proofread and remove mispaired nucleotides. (B)</p> Signup and view all the answers

<p>It is influenced by the geometric fit of nucleotides. (B)</p> Signup and view all the answers

<p>They use parental histones for quick reassembly during replication. (C)</p> Signup and view all the answers

<p>Deficiencies in the DNA polymerase proofreading ability. (C)</p> Signup and view all the answers

<p>Through the mismatch repair system employing various proteins. (C)</p> Signup and view all the answers

<p>To replace RNA primers with DNA (D)</p> Signup and view all the answers

<p>It recognizes the origin of replication (A)</p> Signup and view all the answers

<p>It requires multiple RNA primers for synthesis (B)</p> Signup and view all the answers

<p>Helicase binds to the origin after the pre-replication complex forms (A)</p> Signup and view all the answers

<p>Discontinuous DNA segments synthesized away from the replication fork (A)</p> Signup and view all the answers

<p>DnaB helicase (B)</p> Signup and view all the answers

<p>To stabilize unwound DNA strands during replication (C)</p> Signup and view all the answers

<p>Type I topoisomerases (C)</p> Signup and view all the answers

<p>5' to 3' (B)</p> Signup and view all the answers

<p>During the M and G1 phases of the cell cycle (B)</p> Signup and view all the answers

<p>It introduces or removes supercoils. (B)</p> Signup and view all the answers

<p>It loads the sliding clamp onto DNA. (A)</p> Signup and view all the answers

<p>Two (D)</p> Signup and view all the answers

<p>To unwind the DNA double helix. (D)</p> Signup and view all the answers

<p>The entire complex of active proteins at the replication fork. (B)</p> Signup and view all the answers

<p>To synthesize RNA primers. (A)</p> Signup and view all the answers

<p>Both strands are looped simultaneously. (B)</p> Signup and view all the answers

<p>DNA Polymerase III (A)</p> Signup and view all the answers

The process of copying DNA, essential for cell division.

The theory that each new DNA molecule contains one original strand and one newly synthesized strand.

A type of cell that contains two sets of chromosomes (one from each parent).

A type of cell that contains only one set of chromosomes, found in sperm and egg cells.

A stage in the cell cycle where DNA is replicated.

A small portion of the eukaryotic genome that is replicated independently.

The starting point for DNA replication within a replicon.

The site where the DNA double helix is being separated and new strands are being synthesized.

Specialized regions within the nucleus where replication occurs.

The enzyme responsible for synthesizing new DNA strands during replication.

A topoisomerase that allows rotation around the intact strand of DNA to relieve strain during transcription or replication. It does not require ATP.

A topoisomerase that changes DNA topology by breaking and rejoining double-stranded DNA. They introduce or remove supercoils in DNA, which is critical for untangling and separating intertwined DNA strands during replication and cell division. This process requires ATP.

A prokaryotic Type II topoisomerase that introduces negative supercoils into DNA, making it easier to unwind during replication.

The primary enzyme responsible for replicating DNA in prokaryotes. It is a complex enzyme containing two core DNA polymerase III units, multiple β clamps, and a γ-clamp loading complex. The two core polymerase units replicate DNA by extending the RNA primers on both the leading and lagging strands.

The ring-shaped proteins that allow DNA polymerase to remain attached to the DNA during replication. They ensure that the polymerase doesn't detach from the DNA strand, allowing for continuous synthesis.

A clamp on the leading strand allows for continuous DNA synthesis. On the lagging strand, there is one clamp for each Okazaki fragment

The component of the DNA polymerase III holoenzyme responsible for loading the β-clamp onto the DNA. It is also bound to the helicase.

The entire complex of active proteins that operate at the replication fork. Includes DNA polymerase III holoenzyme, helicase, single-stranded binding proteins (SSBs), and primase. It's essentially the 'replication machine' that produces two new DNA molecules from one original molecule.

A new strand of DNA is made in the 5' to 3' direction. This means that the new nucleotides are added to the 3' end of the growing strand. At the same time, the old strand is being separated (unwound) so that the new strand can be built.

DNA polymerase III is the primary polymerase for replication in prokaryotes. It is responsible for the majority of DNA synthesis.

An enzyme called DNA helicase unwinds the DNA helix, breaking the bonds between the two strands. The unwinding process uses energy from ATP.

These proteins bind to the single-stranded DNA, preventing it from re-annealing (coming back together) so that the new strand can be built.

The RNA primer is a short stretch of RNA nucleotides that is required to initiate DNA synthesis. DNA polymerase III can only add nucleotides to an existing 3' hydroxyl group.

The lagging strand is synthesized in short fragments, called Okazaki fragments, because it is built in the opposite direction of the replication fork. Each fragment requires a separate RNA primer.

The leading strand can be synthesized continuously in the 5' to 3' direction, following the movement of the replication fork.

The origin of replication is a specific sequence within the genome where DNA replication begins.

DNA polymerase III extends the RNA primers laid down by primase on the lagging strand during DNA replication. It continuously adds deoxynucleotides to the primer, resulting in a growing DNA strand.

The lagging strand is looped around DNA polymerase III to ensure both DNA polymerase III and DNA polymerase I, which removes the RNA primers, work in tandem during DNA replication.

DNA Polymerase III releases the lagging strand once it encounters a 5' end of a previously synthesized Okazaki fragment.

DNA Polymerase III continues its journey down the lagging strand template, binding to the template further along its length and elongating DNA from the next RNA primer.

DNA Polymerase I has both exonuclease and polymerase activities. It removes the RNA primers of the Okazaki fragments using its 5' to 3' exonuclease activity and then fills the gaps generated by the RNA primers with dNTs using its polymerase activity.

The enzyme responsible for joining Okazaki fragments during DNA replication.