Chapter 15

DNA polymerase can only work in what direction

5' to 3'

which of the following sequences would result from replication of this DNA template strand? 3'- AAGTCAGT -5'

5'- TTCAGTCA -3'

in an analysis of the nucleotide composition of DNA, which of the following will be found

A + C = G + T

short sequences that allow the initiation of DNA synthesis

Primers

A bacterium is infected with an experimentally constructed bacteriophage composed of the T2 phage protein coat and T4 phage DNA. The new phages produced would have

T4 protein and T4 DNA

What would be the consequence(s) for DNA synthesis if primase were defective?

both leading and lagging strand synthesis would be incomplete (all DNA polymerase require a primer)

eukaryotic telomeres replicate differently than the rest of the chromosomes. this is a consequence of?

gaps left at the 5' end of the lagging strand

3' end

hydroxyl group

which of the following describes the eukaryotic chromosome?

it consists of a single linear molecule of double-stranded DNA plus proteins

which strand of DNA is synthesized toward the middle of the replication bubble

lagging strand

What enzyme covalently connects segments of DNA?

ligase

Benzopyrene in cigarette smoke binds to DNA and distorts its shape, interfering with DNA replication. Which repair mechanism would most likely be used to repair the damage caused by this chemical?

nucleotide excision repair

5' end

phosphate group

Which part of a deoxynucleoside triphosphate (dNTP) molecule provides the energy for DNA synthesis?

phosphate groups

creates a primer for DNA polymerase

primase

which enzyme synthesizes short segments of RNA

primase

The DNA of telomeres has been found to be highly conserved throughout the evolution of eukaryotes. What does this most probably reflect?

that the critical function of telomeres must be maintained

Given the damage caused by UV radiation, the kind of gene affected in those with XP is one whose product is involved with

the ability to excise single-strand damage and replace it

Researchers found E. coli that had mutation rates one hundred times higher than normal. Which of the following is the most likely cause of these results?

the proofreading mechanism of DNA polymerase was unable to add bases to the 3' end of the growing nucleic acid chain

which of the following statements about Okazaki fragments in E. coli is true

they are formed on the lagging strand of DNA

which of the following enzymes is important for relieving the tension in a helix after it unwinds during DNA synthesis

topoisimerase

Single-stranded DNA molecules are said to be antiparallel when they are lined up next to each other but oriented in opposite directions

true

Suppose you are provided with an actively dividing culture of E. coli bacteria to which radioactive thymine has been added. What would happen if a cell replicates once in the presence of this radioactive base?

DNA in both daughter cells would be radioactive

what catalyzes DNA synthesis

DNA polymerase

which of the enzymes removes the RNA nucleotides from the primer and adds equivalent DNA nucleotides to the 3 prime end of Okazaki fragments

DNA polymerase I