BIO 315- Quiz 2

During eukaryotic replication, CAF-1 mediates the immediate histone packaging of DNA based on its interaction with which protein in the replication complex?

PCNA

You have discovered and "Exo-" mutant form of DNA polymerase in which the 3'-to-5' exonuclease function has been destroyed but the ability to join nucleotides together is unchanged. Which of the following properties do you expect the mutant polymerase to have? -It will polymerize in both the 5′-to-3′ direction and the 3′-to-5′ direction -It will polymerize more slowly than the normal Exo+ polymerase. -It will fall off the template more frequently than the normal Exo+ polymerase. -It will be more likely to generate mismatched pairs -It will polymerize in both the 5′-to-3′ direction and the 3′-to-5′ direction and will polymerize more slowly than the normal Exo+ polymerase.

-It will be more likely to generate mismatched base pairs

In bacgteria, post-replicative mismatch repair of incorrectly added nucleotides after DNA replication is dependent on the detectin of which of the following? -Acetylation of daughter DNA strand -Methylation of the parental DNA strand -Acetylation of parental DNA strand -Methylation of daughter DNA strand -Methylation of histones

-Methylation of the parental DNA strand

In terms of DNA structure and composition, which of the following is true? -Bases are found on the outside of the DNA helix -DNA strands of the double helix run parallel to each other -Nucleotides of a DNA strand are linked by 3',5'-phosphodiester bonds -C and G pair with 2 hydrogen bonds -Pyrimidines are A and T

-Nucleotides of a DNA strand are linked by 3',5'-phosphodiester bonds

Which of the following statements concerning DNA is true? -Large structural changes in the human genome are more common than single nucleotide changes. -The melting temperature of DNA increases as its GC content increases -Packaging of DNA into the nucleus is dependent upon positive supercoiling. -Most proteins interact with DNA along its minor groove. -Type I topoisomerases make a nick in both strands of the DNA helix

-The melting temperature of DNA increases as its GC content increases

With respect to genome structure and stability, all of the following statements are true except: -The most common type of genetic variability in humans is from single nucleotide differences. -Genome complexity in terms of size can be determined from DNA renaturation. -Gene families are represented in the non-repeated fraction of eukaryotic DNA. -Transposons have an RNA intermediate and require reverse transcriptase. -Movement of transposons require the enzyme transposase.

-Transposons have an RNA intermediate and require reverse transcriptase

Bacterial DNA polymerase I exhibits what type of activity that is lacking in DNA polymerase III?

5' to 3' exonuclease activity

Where would DNA polymerase III be able to add nucleotides in the growing DNA strands during DNA replication in bacterial DNA?

At the 3' ends in the leading and lagging strand

You are a viroligist interested in studying the evolution of viral genomes. You are studying two newly isolated viral strains and have sequenced their genomes. You find that the genome of strain 1 contains 25% A, 45% G, 20% C, and 10% T. You report that you have isolated a virus with a single-stranded DNA genome. Based on what evidence can you make this conclusion?

Double-stranded genomes have equal amounts of A and T

Methodology used to locate the position of a gene or sequence along a chromosome

Fluorescent in situ hybridization

In mammalian cells, high energy sources can induce double-stranded breaks in the DNA duplex to stimulate repair. Which of the repair mechanisms would ensure the greates chance of not introducing mutations at the repair site?

Homologous recombination

In bacterial replication, what is the function of primase?

Lays down RNA primer needed for replication

In mammalian cells, what double-stranded DNA break repair mechanism relies on the activity of Ku proteins, DNA-PKcs, and DNA ligase?

Non-homologous end joining

During eukaryotic DNA replication, which DNA polymerase is found in the primase complex and helps synthesis primers needed for replication of the lagging strand?

alpha

What protein adds the beta-clamp to the newly primed DNA on the lagging strand so that DNA polymerase III can begin the synthesis of the next Okazaki fragment?

gamma-clamp loader