BCHM 4360 EXAM 1 ACTUAL QUESTIONS AND

BCHM 4360 EXAM 1 (ACTUAL / ) QUESTIONS AND

VERIFIED ANSWERS 100% PASS

Histidine gene - ____Answers----A gene present on the plasmid that allows yeast cells to survive without histidine.

DNA replication - ____Answers----The complete, faithful copying of the DNA comprising the cell's chromosomes.

Semi-conservative - ____Answers----Each strand of the parental double helix acts as a template for synthesis of a new daughter strand, resulting in two copies each comprised of one parent and one daughter strand.

Replication bubble - ____Answers----A structure formed during DNA replication where replication moves away from the origin in both directions.

DNA synthesis direction - ____Answers----DNA synthesis on each strand occurs in the 5' - 3' direction.

Leading strand - ____Answers----The strand where replication is continuous.

Lagging strand - ____Answers----The strand where replication is discontinuous.

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Three phases of DNA replication - ____Answers----Initiation, elongation, termination.

Origin of replication - ____Answers----The location recognized by an initiator protein that opens up the double helix and recruits helicases.

DNA helicases - ____Answers----Enzymes that unwind the helix to expose ssDNA.

ssDNA-binding proteins - ____Answers----Proteins that coat the ssDNA opened up via helicase to prevent anything besides replication from occurring.

Initiation control - ____Answers----Controlled to occur only once per cell cycle; multiple initiations typically result in problems.

DNA synthesis requirement - ____Answers----DNA synthesis needs a primer and can only add nucleotides to the existing 3' hydroxyl group.

RNA primer - ____Answers----A short RNA strand synthesized by primase required for DNA synthesis.

Nucleosome remodeling - ____Answers----Nucleosome remodeling enzymes must be used to move the nucleosomes out of the way before DNA replication can be initiated. 2 / 4

Sliding clamp - ____Answers----Required for DNA replication to prevent DNA Polymerase from falling off before it finishes transcribing.

Sliding clamp recruitment - ____Answers----The sliding clamp is recruited directly after the RNA primer is synthesized.

Clamp loader - ____Answers----The component necessary for DNA Polymerase to be associated with DNA along with the sliding clamp.

ATP hydrolysis - ____Answers----Used by the clamp loader to reshape the clamp, bind DNA, and then close the clamp again.

DNA clamp necessity - ____Answers----The DNA clamp is not necessary for high fidelity but is necessary for high processivity.

Termination of DNA replication - ____Answers----Occurs when different forks meet, the fork reaches the end of a linear chromosome, or polymerase meets the previously replicated strand.

Exonuclease - ____Answers----Part of the DNA polymerase that is responsible for correcting errors.

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Different polymerases - ____Answers----Cells have a number of different polymerases with different dissociation lengths; some go very long without dissociating for replication, while others go only a few nucleotides for repair.

DNA Polymerase - ____Answers----A tube-shaped enzyme that recognizes mismatches in DNA by detecting steric hindrance and uses exonuclease to fix mistakes.

Polymerase III - ____Answers----The primary polymerase involved in DNA replication in bacteria.

Polymerases delta and epsilon - ____Answers----The primary polymerases involved in DNA replication in eukaryotes.

Catalytic site - ____Answers----The most highly conserved region of DNA polymerase responsible for nucleotide addition.

Shape of DNA polymerase - ____Answers----Resembles a right hand, where growing dsDNA fits into the palm and ssDNA winds through the fingers.

Active site of DNA Polymerase - ____Answers----Contains carboxylate groups of two aspartate residues coordinated with two magnesium ions.

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