Chapter 11 Genetics Quizlet

In bacterial DNA replication, each bacterial chromosome has only _____ origin of replication

1

The leading strand has ____ RNA primer made at the _____. DNA polymerase ____ attaches nucleotides in a 5' to 3' direction as it slides toward the ______ of the replication fork.

1 , origin , DNA polymerase III l, opening

Functions of Key Proteins invovled with Bacterial DNA replication: 1) DNA helicase breaks the ______ bonds between the DNA strands 2) DNA gyrase alleviates ______ supercoiling 3) _____-stranded binding proteins keep the ______ strands apart 4) ______ synthesizes an RNA primer 5) DNA polymerase III synthesizes a _____ strand of DNA 6) DNA polymerase I excises the RNA ____ and fills it in with _____. 7) DNA ligase ______ links the _____ fragments together

1) hydrogen 2) positive 3) Single , parental 4) Primase 5) daughter 6) primers , DNA 7) covalently , Okazaki

DNA polymerase III makes only one mistake per ____ bases made

10^8

In DNA polymerase, the __' ends cannot be replicated.

3'

DNA polymerases can attach nucleotides only in the __' to __' direction, but the two strands are anti-____ and go in opposite directions. This problem is overcome by synthesizing the new strands both toward, and away from the replication fork, creating two new _____ strands.

5 to 3 , parallel , daughter

In bacterial DNA replication, the DNA helicase is composed of ____ subunits, travels along the DNA in the ___' to ___' direction, and uses energy from _____.

6 , 5 to 3 , ATP

In bacterial DNA replication, DNA adenine methyltransferase (Dam) methylates the ____ on both strands, but the _____ strand is not immediately methylated, as it takes several minutes to become methylated.

A , daughter

In E. coli , three types of DNA sequences in oriC are functionally significant, which are the ___-____ region, _____ boxes, and ______ methylation sites.

AT-rich , DnaA , GATC

DNA polymerase ____ is composed of a single polypeptide, and it removes the RNA primers and replaces them with DNA.

DNA polymerase I

DNA polymerase ____ removes the RNA primers and fills the resulting gap with DNA. It uses a 5' to 3' ______ activity to digest the RNA and 5' to 3' ______ activity to replace it with DNA, but after the gap is filled, a _____ bond is still missing

DNA polymerase I , exonuclease , polymerase , covalent

DNA polymerase _____ is responsible for most of the DNA replication, and is composed of 10 different subunits

DNA polymerase III

______ _____ occurs very quickly, very accurately and at the appropriate time in the life of the cell

DNA replication

_______ _______ is the process by which the genetic material is copied.

DNA replication

In bacterial DNA replication, DnaA proteins bind to _____ box sequences and to eachother, and additional proteins that cause the DNA to ____ also bind. This causes to the region to ____ around the DnaA proteins and _____ the AT-rich region.

DnaA , bend , wrap , separates

In _____ there are five proteins with polymerase activity, which are DNA polymerases I, II, III, IV and V. DNA polymerases I and III are used for _____ replication, DNA polymerases II, IV and V are used for DNA ____ and ______ of damaged DNA

E. coli , normal , replication , repair

In E. coli, _____ methylation sites are spread throughout regions.

GATC

______ cells contain well over a dozen different DNA polymerases

Mammalian

The enzyme known as ________ uses ________ and separates the DNA strands at the replication fork. a) helicase, ATP b) helicase, GTP c) gyrase, ATP d) gyrase, GTP

a) helicase, ATP

Telomeres tend to shorten in ____ dividing cells, as telomeres DNA is about _____ bp at birth, and can shorten to ____ bp in elderly person

actively , 8,000 bp , 1,500 bp

The lagging strand synthesis occurs in the 5' to 3' direction, but occurs ____ from the replication fork, and _____ RNA primers are required. DNA polymerase III uses the RNA primers to synthesize small DNA _____ (1000 to 2000 nucleotides in bacteria, 100-200 in eukaryotes) , which are called _____ fragments.

away , many , fragments , Okazaki

The model that correctly describes the process of DNA replication is a) the conservative model. b) the semiconservative model. c) the dispersive model. d) all of the above.

b) the semiconservative model.

DNA replication proceeds ______ from many origins of replication

bidirectionally

In bacterial DNA replication, synthesis of DNA proceeds _______ around the bacterial chromosome

bidirectionally

In synthesizing a new DNA strand, the DNA helicase separates the two DNA strands by _____ the ______ bonds between them, which generates _____ supercoiling ahead of each replication fork, allowing DNA gyrase to travel ahead of the DNA helicase and alleviate the _____.

breaking , hydrogen , positive , supercoils

The complementarity of DNA strands is based on a) the chemical properties of a phosphodiester linkage. b) the binding of proteins to the DNA. c) the AT/GC rule. d) none of the above.

c) the AT/GC rule.

In DNA polymerase III , the alpha subunit _____ bond formation between _____ nucleotides, which is also called DNA synthesis. The other 9 fulfill other functions.

catalyzes , adjacent

The first fidelity mechanism is from stability of proper base pairs, as _____ base pairs have much higher stability than mismatched pairs, stability of base pairs only accounts for part of the fidelity, and ____ rate for mismatched base pairs is 1 per _____ nucleotides.

complementary , error , 1,000

Bacterial DNA polymerases may vary in their subunit ______ , but they all have a similar _____ subunit.

composition , catalytic

The second fidelity mechanism is _______ of the DNA polymerase active site, as _____ distortion caused by mispairing prevents incorrect nucleotide fitting properly in active site. This induced-fit phenomenon _____ the error rate to a range of 1 in 100,000 to 1 million

configuration , helix , decreases

DNA polymerases can only synthesize DNA in the 5' to 3' direction, so synthesis of the leading strand is ______ , and that of the lagging strand is _____.

continuous , discontinuous

To make a new DNA strand, which of the following is necessary? a) A template strand b) Nucleotides c) Heavy nitrogen d) Both a and b

d) Both a and b

The third fidelity mechanism is proofreading function of DNA polymerase, as DNA polymerases can identify a mismatched nucleotide and remove it from the ______ strand. The enzyme uses a __' to __' exonuclease activity to digest the newly made strand until the mismatched nucleotide is removed. After this, DNA synthesis then resumes in the __' to __' direction.

daughter , 3' to 5' , 5' to 3'

DNA polymerase ______ are responsible for synthesizing the DNA.

enzymes

DNA replication exhibits a high degree of _____ , meaning mistakes during the process are extremely rare.

fidelity,

In bacterial DNA replication, the two replication _____ eventually meet at the _____ side of the bacterial chromosome, which ends replication.

forks, opposite

Telomeric sequences typically consist of several ____ nucleotides and many thymine nucleotides

guanine , thymine

The primosome coordinates the actions of the ____ and _____.

helicase , primase

In bacterial DNA replication, after separating from the AT-rich region, two DNA _____ bind to the _____. DnaC proteins _____ in this process.

helicases , origin , assist

In DNA polymerase III , the complex of all 10 subunits is referred to as the DNA polymerase III _______.

holoenzyme

Cancer cells commonly carry mutations _____ the activity of telomerase, which _____ both the telomere from shortening and senescence. This may be a target for anti-cancer drug treatments.

increasing , prevents

DNA polymerases cannot ______ DNA synthesis, but the problem is overcome when the RNA primers are synthesized by ______.

initiate , primase

Huberman and Riggs concluded that multiple regions had _____ replication

initiated

In bacterial DNA replication, _____ of replication only occurs efficiently on fully _____ DNA, as the second round of initiation is ______.

initiation , methylated , blocked

In DNA synthesis, the _____ strand is looped out.

lagging

Two DNA polymerase III proteins act in concert to replicate both the ____ and _____ strands. The two proteins form a _____ DNA polymerase that moves as a unit ______ the replication fork

leading , lagging , dimeric , toward

After the gap is filled, DNA _____ catalyzes the formation of a phosphodiester bond, which connects the DNA _____.

ligase , fragments

DNA replication in eukaryotes is more complex, as it contains large _____ chromosomes, the _____ is tightly packed within nucleosomes, and it has a more _____ cell cycle regulation.

linear , chromatin , complicated

In the lagging strand synthesis, the lagging strand is _____ , allowing the attached DNA polymerase to synthesize the _____ ______ in the normal 5' to 3' direction. The polymerase synthesizing the lagging strand is also moving _____ the replication fork. Upon completion of an Okazaki fragment, the enzyme releases the lagging template strand, and the _____ _____ complex then reloads the polymerase at the next RNA _____ , and another _____ is then formed. The process is repeated over and over.

looped , Okazaki fragments , toward , clamp loader , primer , loop

Eukaryotes have long linear chromosomes that require _____ origins of replication to ensure that the DNA can be replicated in a reasonable amount of _____.

multiple , time

Alpha (a), Delta (d), Epsilon (e) and Gamma (g) have the primary function of replicating DNA. Alpha, delta, and epsilon replicate ______ DNA, while gamma replicates ______ DNA

nuclear , mitochondrial

The origin of replication in E. coli is termed _____ , which stands for origin of Chromosomal replication.

oriC

In bacterial DNA replication, DNA synthesis begins at a site termed the _____ of _______.

origin of replication

DNA polymerases catalyzes the formation of a covalent (ester) bond between the Innermost _____ group of the incoming deoxyribonucleoside triphosphate and the 3'-OH of the _____ of the previous deoxynucleotide

phosphate , sugar

In DNA polymerase catalyzation, the last two _____ of the incoming nucleotide are released in the form of ______.

phosphates , pyrophosphate

DNA helicase and primase are ______ bound to each other to form a complex called the _______ , which better coordinates the actions of helicase and primase.

physically , primosome

DNA ______ are the enzymes that catalyze the attachment of nucleotides to synthesize a new DNA strand

polymerases

After bases hydrogen bond with individual nucleotides, short RNA ______ , which are about 10-12 nucleotides , are synthesized by ______.

primers , primase

Telomerase contains _____ and RNA, and the RNA is complementary to the _____ sequence found in the telomeric repeat. This allows the telomerase to bind to the 3' overhang.

protein , DNA

In bacterial DNA replication , GATC methylation sites are involved in _____ replication, as they need to ensure only ____ round of replication occurs.

regulating , 1

DNA polymerase III is responsible for most of the DNA _____, and is composed of ____ different subunits.

replication , 10

Leading and lagging strand synthesis are linked by the ______ structure

replisome

In bacterial DNA replication, after two DNA helicases bind to the origin, the DNA helicase _____ the DNA in both directions, creating ____ replication forks, which initiates ________ replication.

separates , 2 , bidirectional

Cells become senescent when telomeres are ______ , as they lose their ability to divide. Insertion of highly active ______ can block senescence.

short , telomerase

In synthesizing a new DNA strand, ______-strand binding proteins bind to the separated DNA strands to keep them apart, and _____ are exposed, which allows them to hydrogen bond with individual _______.

single , bases , nucleotides

DNA polymerase I is composed of a _____ polypeptide, and it removes the RNA _____ and replaces them with DNA.

single , primers

Fidelity in DNA replication is high because of the _____ of base pairing, the _____ of the DNA polymerase active site, and the _____ function of DNA polymerase

stability, structure , proofreading

RNA primers _____ DNA synthesis, are typically ____-____ nucleotides in length, have a _____ strand with a single primer, a ______ strand with multiple primers, and are eventually removed and replaced with DNA.

start , 10-12 , leading , lagging

Telomeric sequences consist of moderately repetitive ____ arrays with a __' overhang that is 12-16 nucleotides long

tandem , 3'

The cell solves the problem of DNA polymerases two unusual rules by adding DNA sequences to the ends of _____.

telomeres

In DNA replication, original DNA strands are used as _____ for the synthesis of new strands.

templates

The primosome is physically associated with ____ DNA polymerase holoenzymes to form the ______.

two , replisome