Chapter 14v2

Three items needed for DNA replication

Nucleotides, Polymerase, Template

A chromosome is primarily composed of

Proteins, DNA

Not involved in the unwinding of DNA during replication

RNA polymerase

nonspecific repairmechanism

Repair multiple kinds of lesions in DNA

Phosphodiester backbone

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

Okazaki fragment

Short fragments of DNA that are a result of the synthesis of the lagging strand during DNA replication.

Components of a nucleotide

Sugar, Phosphate, Nitrogenous base

Leading strand

Synthesized continuously

Lagging strand

Synthesized in small fragments that are later connected

In DNA complimentary base pairing A pairs with __ and C pairs with __

T,G

specific repair mechanism

Target a single kind of lesion in DNA and repair that damage

Wilkins

The DNA fibers Franklin used in her x-ray diffraction studies came from

a sugar phosphate backbone a helical structure two groves (major & minor)

The DNA structure proposed by Watson and Crick involves

Double helix

The interaction of two strands of DNA via hydrogen bonds is the

double helix

The level of DNA structure that resembles a spiral staircase is the

The DNA fibers Franklin used in her x-ray diffraction studies came from

Wilkins

Prokaryotic replication begins at

a single origin

Features of the Watson and Crick model include

helical structure, sugar phosphate backbone, and a double stranded structure

Adjacent nucleotides in the same DNA strand are held together by covalent bonds called

phosphodiester bonds

Enzyme that can repair UV damage by binding to a thymine dimer and cleaving it, therefore restoring two thymines

photolyase

The enzyme DNA ___ covalently links nucleotides to synthesize new DNA strands together during DNA replication

polymerase

Target a single kind of lesion in DNA and repair that damage

specific

The ______ is part of the replisome composed of primase, helicase, and accessory proteins that prime the lagging strand

primosome

The function of telomeres are to

protect the end of chromosomes

The DNA controlled by an origin is called a

replicon

Meselson and Stahls data supports which DNA model?

semiconservative

- synthesize primer using primase -synthesize DNA - Replace RNA primers with DNA - Seal nicks in the DNA

steps of lagging strand synthesis:

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

semiconservative replication

Differences in prokaryotic and eukaryotic replication

structure of chromosome, number of origins of replication, complexity of enzymology

Griffith performed experiments related to

studying transformation in bacteria

The term ____ refers to the coiling of two DNA strands leading to torsional strain

supercoiling

Contains a small, internal piece of RNA, which is used as a template to extend the end of a linear DNA molecule

telomerase

______ are short protective repeats of DNA on the ends on eukaryotic chromosomes which are generated by the enzyme ______

telomeres, telomerase

DNA repair mechanisms have evolved because

there is no way for cells to avoid mutagens

Why do eukaryotic cells have multiple origins of replication

to ensure timely replication of multiple, relatively large chromosomes

helicase

unwinds the double helix

adenine guanine cytosine uracil

used in RNA?

Phages are a type of _______ that infect _______ cells. causing them to lyse

virus, bacteria

Match each element of the nucleotide to the sugar carbon atom it is attached to

1' - Nitrogen base 3' - OH group 5' - Phosphate group

Part of the Watson and Crick model

1. Each DNA is composed of 2 phosphodiester strands 2. Each DNA molecule is composed of two strands that run antiparallel

DNA primase

1. Makes a primer about 10-20 nucleotides in length 2. Makes a primer of RNA complimentary to DNA

Excision repair for DNA

1. Recognition of damaged 2. Removal of damaged region 3. re synthesis of the region from the undamaged DNA

List several differences in prokaryote vs eukaryote replication

1. Structure of chromosome (linear vs circular) 2. Complexity of enzymology 3. Number of origins of replication

Steps of lagging strand synthesis

1. Synthesize primers using primase 2. Synthesize DNA 3. Replace RNA primers with DNA 4. Seal nicks in the DNA

Two general categories of non-specific repair pathways

1. error-free 2. error-prone

How many hydrogen bonds are formed between the nucleotides (A,T,G,C) in a DNA backbone

2

X-ray diffraction was used to determine that the diameter of DNA is

2nm

How many hydrogen bonds between G and C in DNA

3

DNA can only be synthesized in this direction

5'-3' (five prime to three prime)

Bacterial DNA is typically replicated as

A single replicon

RNA is composed of which nucleotide

A,C,G,U

Chargaff's Rule with nucleotides

AT are in same amount as CG

Phosphodiester

Adjacent nucleotides in the same DNA strand are held together by covalent bonds known as __________ bonds

Determined that DNA was the genetic material by studying the transforming principle

Avery, MacLeod and McCarty

Along with Griffith, these individuals also studied bacterial transformation

Avery, MacLeod, McCarty

Why do we say DNA or RNA strand has an intrinsic polarity?

Because it has a free 5' Phosphate at one end and a free 3' OH group at the other end

How are origins of replication adjusted in eukaryotic cells, so that in early embryonic development of the organism, DNA can replicate faster?

Cells can increase the number of origins used during early development

Thymine

Chargaff's experiment showed that the amount of adenine in a sample was always the amount of

Avery, MacLeod, and McCarty isolated a substance which had transforming activity. What enzyme destroyed this substance's ability to transform bacteria cells?

DNA digesting enzyme

Meselson and Stahl

Determined a method for the replication of genetic material through three different mechanisms

Major Significance of Hershey/Chace experiment

Determined that DNA was genetic material by studying the T2 bacteriophage

The level of DNA structure that resembles a spiral staircase is

Double helix

Determined a method for the replication of genetic material

Messlson and Stahl

x-ray diffraction analysis

Franklin determined that the structure of DNA was helical based

A bacteriophage contains

Genetic material, a protein coat

Showed that there was a transforming principle that could be passed between bacterial cells

Griffith

Determined that DNA was genetic material by studying the T2 bacteriophage

Hershey and Chase

2

How many hydrogen bonds are formed between adenine and thymine in the double DNA helix?

3

How many hydrogen bonds form between cytosine and guanine in the DNA double helix?

Function of DNA polymerase in E. coli

I. Acts on lagging strand, removes primers and replaces with DNA II. Not involved in replication but used for DNA repair III. The main replication enzyme

- phosphodiester - hydroxyl

In DNA, consecutive nucleotides are linked via ____________ bonds, which are made between the 5' phosphate of one nucleotide and the3' ______________ group of another nucleotide.

Antiparallel

The term used to describe two DNA strands that run in opposite directions from each other is

to ensure timely replication of multiple, relatively large chromosomes

Why do eukaryotic cells have multiple origins of replication?

indicate the four nitrogenous bases used in DNA

adenine, cytosine, guanine, and thymine

oriC

are more sequence -specific?

DNA'S phosphodiester ________ is composed of sugars and phosphates

backbone

DNA backbone is composed of

phosphate groups and sugars

Genes, which contain trait specifying information on

chromosomes

The major significance of the Hershey Chase experiments is that they

determined that DNA in the genetic material

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

differences in prokaryotic and eukaryotic replication

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

diffraction

an enzyme that cuts the bonds within a polynucelotide chain

endonuclease

Main eukaryotic DNA polymerases that extend DNA are

epsilon and delta

can only degrade from the end of the nucleic acid polymer

exonuclease

The enzyme DNA _____ is the topoisomerase involved in DNA replication

gyrase

The primary purpose of the meselson and Stahl experiments was to determine

how DNA replicates

The three phases of DNA replication are

initiation, elongation, and termination

Primary reason bacteriophage was the ideal model for Hersey-Chase experiment is because

it is made of only protein and DNA

Synthesized in small fragments that are later connected

lagging strand

Synthesized continuously

leading strand

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

linear

DNA replication in eukaryotic cells is complicated by

linear chromosomes

In any aging cell the activity of telomerase would be

low

Radiation, UV light, X-rays, and chemicals in the environment cause mutations in DNA and are therefore called

mutagens

What isotope did Meselson and Stahl use in their experiments

nitrogen

Repair multiple kinds of lesions in DNA

nonspecific

During semiconservative DNA replication

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

Which origins are more sequence-specific

oriC

The components of a nucleotide include

phosphate group, sugar, nitrogenous base