ch14

leading strand lagging strand

synthesized continuously synthesized in small fragments that are later connected

specific nonspecific

target a single kind of lesion in DNA and repair that damage repair multiple kinds of lesions in DNA, using a single mechanism

Griffith performed experiments, which demonstrated

transformation in bacteria

Franklin determined that the structure of DNA was helical based on

x-ray diffraction analysis

What type of repair mechanism is responsible for removing bases that were incorrectly inserted into DNA during replication?

Mismatch repair

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.

PCNA

Polymerase

attaches a nucleotide to the 3' end of the DNA strand

DNA's phosphodiester _____ is composed of sugars and phosphates.

backbone

The two main eukaryotic DNA polymerases that extend DNA are

epsilon delta

The enzyme ____ uses ATP to unwind the DNA template.

helicase

The enzyme _____ uses ATP to unwind the DNA template.

helicase

DNA replication in eukaryotic cells is complicated by the fact that eukaryotic cells have

linear chromosome

____ repair is responsible for removing bases that were incorrectly incorporated into DNA during replication.

Mismatch

What is the name of the regions at the ends of eukaryotic chromosomes?

Telomeres

Which of the following are short repeats of DNA on the ends of eukaryotic chromosomes?

Telomeres

Choose all characteristics of the transforming substance isolated by Avery, MacLeod and McCarty.

The elemental composition of the substance was very similar to that of DNA.--- RNA-digesting enzymes did not affect its transforming ability.----- Protein-digesting enzymes did not affect its transforming ability.------ DNA-digesting enzymes destroyed its transforming ability.

An ______ cuts DNA internally and an ______ cuts at the ends of DNA.

endonuclease; exonuclease

Based on replication proteins, DNA replication in archaea is most similar to that of

eukaryotes

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:

eukaryotic

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

Radiation, UV light, x-rays, and chemicals in the environment can cause mutations in DNA and are therefore referred to as

mutagens

Of the following list, which 3 items are required for DNA replication

nucleotides polymerase template

Select all of the following that are components of a nucleotide.

sugar phosphate group nitrogenous base

The DNA backbone is composed of (choose all that apply)

sugars. phosphate groups.

Short, repeated sequences of DNA are characteristic of

telomeres

Griffith's experiments were important because they showed

that the genetic material could be passed from one cell to another

primase

makes a 10-12 bp complementary primer to the DNA

Agents that cause mutation are known as

mutagens

Which types of cells have more than one origin of replication?

Eukaryotes

In which of the following chromosomal entities are an individual's traits specified?

Genes

Which of these is not required for DNA replication?

NADPH

The function of telomeres is to

protect the ends of chromosomes

Which enzymes did Avery, MacLeod, and McCarty use in order to identify the genetic material?

DNA digesting enzymes RNA digesting enzymes protein digesting enzymes

The enzyme that relieves DNA supercoiling ahead of the replication fork is

DNA gyrase

Which of the following facilitates the reversal of damage to our hereditary material before a permanent mutation can occur?

DNA repair systems

In their experiments, Avery, MacLeod, and McCarty isolated a substance, which had a transforming activity. Which of the following destroyed that substance's ability to transform bacterial cells?

DNA-digesting enzymes

Which of the following enzymes involved in DNA replication are found at the replication fork in all three types of cells (bacterial, archaeal, and eukaryotic)? Choose all that apply.

Helicase Clamp loader Polymerases Sliding clamp Primase

The experiments with radioactively labeled phage that showed that DNA was the genetic material were performed by

Hershey and Chase

Why do eukaryotic cells have multiple origins of replication?

To ensure timely replication of multiple, relatively large chromosomes

Features of the Watson and Crick model include

a helical structure; a sugar phosphate backbone; a double stranded structure

Bacterial replication (for example in E. coli) begins at

a single origin

The DNA structure proposed by Watson and Crick involves

a sugar phosphate backbone two grooves (major and minor) a helical structure

Nucleotides contain a sugar, a phosphate, and a nitrogenous

base

Genes, which contain trait specifying information, are located on

chromosomes

The major significance of the Hershey and Chase's experiments is that they

determined that DNA is the genetic material

Franklin used x-ray ___ to suggest that DNA has a helical structure.

diffraction/crystallography

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

During semiconservative DNA replication

one of the strands in each new double helix comes from the original molecule, and one is newly synthesized.

Repeating sugar and phosphate units in a single DNA strand make up the

phosphodiester backbone.

In the replisome, the ___ is composed of primase, helicase, and accessory proteins that prime the lagging strand.

primosome

In the replisome, the____ is composed of primase, helicase, and accessory proteins that prime the lagging strand.

primosome

The results of the Hershey and Chase experiments suggested that DNA was the genetic material because

radioactive bacteriophage DNA was found in the cytoplasm of bacterial cells

gyrase

relieves coiling in DNA strands ahead of the replication fork

The DNA controlled by an origin is called a

replicon

DNA replication that leads to the production of double helices with one parental strand and one newly synthesized strand is consistent with

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

single-strand binding proteins

The two general categories of DNA repair are

specific nonspecific

List several differences in prokaryotic and eukaryotic replication.

structure of chromosome (linear vs. circular) complexity of enzymology number of origins of replication

The enzymes in the replisome are active on

the leading and the lagging strands

DNA repair mechanisms have likely evolved because

there is no way for cells to avoid exposure to mutagens

Helicase

unwinds the double helix