Biology 101 - Chapter 14
What is the name of the subunit that acts as the sliding clamp, which keeps the replicating enzyme complex attached to the template in eukaryotic cells. a.) PCNA b.) Primase c.) DNA polymerase II d.) Replicon
a.) PCNA
Of the following list, which 3 items are required for DNA replication a.) template b.) polymerase c.) amino acids d.) nucleotides e.) ribose
a.) Template b.) Polymerase d.) Nucleotides
Repeating sugar and phosphate units in a single DNA strand make up the a.) double backbone helix. b.) nucleotides. c.) phosphodiester backbone.
c.) phosphodiester backbone.
The enzyme ______ uses ATP to unwind the DNA template.
helicase
In the replisome, the _________ is composed of primase, helicase, and accessory proteins that prime the lagging strand
primosome
List several differences in prokaryotic and eukaryotic replication.
- structure of chromosome (linear vs. circular) - number of origins of replication - complexity of enzymology
Why do eukaryotic cells have multiple origins of replication? a.) To ensure timely replication of multiple, relatively large chromosomes b.) So that the new strands can meet at the end of the circular chromosomes c.) So that both strands of DNA can serve as a template to produce new strands
a.) To ensure timely replication of multiple, relatively large chromosomes
Bacterial replication (for example in E. coli) begins at a.) a single origin b.) 2-3 origins c.) multiple (>3) origins
a.) a single origin
An ______ cuts DNA internally and an ______ cuts at the ends of DNA. a.) endonuclease; exonuclease b.) exonuclease; endonuclease
a.) endonuclease; exonuclease
Based on replication proteins, DNA replication in archaea is most similar to that of a.) eukaryotes b.) bacteria
a.) eukaryotes
Agents that cause mutation are known as a.) mutagens b.) sarcomas c.) nucleases d.) carcinomas
a.) mutagens
Which types of cells have more than one origin of replication? a.) Prokaryotes b.) Eukaryotes c.) Prokaryotes and eukaryotes
b.) Eukaryotes
Which of these is not required for DNA replication? a.) Nucleotides b.) NADPH c.) Template d.) Polymerase
b.) NADPH
The two main eukaryotic DNA polymerases that extend DNA are a.) alpha b.) delta c.) epsilon d.) gamma
b.) delta c.) epsilon
This type of primase is a combination of RNA polymerase and DNA polymerase that makes short RNA primers and then extends them with DNA to produce the final primer: a.) bacterial b.) eukaryotic c.) archaeal
b.) eukaryotic
During semiconservative DNA replication a.) one of the new daughter double helix is made of the two original strands, while the other one is made of two new strands b.) one of the strands in each new double helix comes from the original molecule, and one is newly synthesized. c.) random portions of each new double helix come from the original molecule or are newly synthesized
b.) one of the strands in each new double helix comes from the original molecule, and one is newly synthesized.
The enzymes in the replisome are active on a.) the leading strand only b.) the leading and the lagging strands c.) the lagging strand only
b.) the leading and the lagging strands
DNA's phosphodiester ___________ is composed of sugars and phosphates.
backbone
What type of repair mechanism is responsible for removing bases that were incorrectly inserted into DNA during replication? a.) Photorepair b.) Exonuclease repair c.) Mismatch repair d.) SOS response
c.) Mismatch repair
DNA replication in eukaryotic cells is complicated by the fact that eukaryotic cells have a.) small amounts of DNA b.) circular chromosomes c.) linear chromosomes
c.) linear chromosomes
The DNA backbone is composed of (choose all that apply) a.) nitrogenous bases b.) amino acids c.) phosphate groups d.) sugars
c.) phosphate groups d.) sugars
DNA replication that leads to the production of double helices with one parental strand and one newly synthesized strand is consistent with a.) conservative replication b.) dispersive replication c.) semiconservative replication
c.) semiconservative replication
When the double stranded DNA helix is unwound, two single strands of DNA are formed. These strands have to be stabilized because their hydrophobic bases are exposed to water. The proteins that stabilize the two single strands are called a.) RNA polymerases b.) helicase proteins c.) single-strand binding proteins d.) topoisomerase proteins
c.) single-strand binding proteins
Griffith's experiments were important because they showed a.) that proteins could not be the genetic material of cells b.) the true identity of the genetic material c.) that the genetic material could be passed from one cell to another d.) how genetic material was inherited in bacteria
c.) that the genetic material could be passed from one cell to another
Griffith performed experiments, which demonstrated a.) that DNA is made of nucleotides. b.) the existence of viruses, which infect bacteria. c.) transformation in bacteria.
c.) transformation in bacteria.
The enzyme that relieves DNA supercoiling ahead of the replication fork is a.) polymerase b.) ligase c.) helicase d.) DNA gyrase
d.) DNA gyrase
Short, repeated sequences of DNA are characteristic of a.) origins of replication b.) nucleases c.) DNA polymerase d.) telomeres
d.) telomeres
E. coli polymerases I, II, and III have 3' to 5' _____________ activity, which provides them with a proofreading function, i.e. they can remove a mispaired base.
exonuclease
Match these enzymes involved in DNA replication with their function. Instructions - helicase - gyrase - primase - polymerase - unwinds the double helix - relieves coiling in DNA strands ahead of the replication fork - attaches a nucleotide to the 3' end of the DNA strand - makes a 10-12 bp complementary primer to the DNA
helicase -> unwinds the double helix gyrase -> relieves coiling in DNA strands ahead of the replication fork primase -> makes a 10-12 bp complementary primer to the DNA polymerase -> attaches a nucleotide to the 3' end of the DNA strand
Match the following strands with the type of synthesis. leading strand lagging strand synthesized continuously synthesized in small fragments that are later connected
leading strand - synthesized continuously lagging strand - synthesized in small fragments that are later connected
During DNA replication, the ________ strand is synthesized continuously while the _________ strand is synthesized as small fragments that are connected to each other to form a continuous strand.
leading, lagging