Exam 4

Question 1

Building blocks of DNA

Answer 1

Deoxynucleotide triphosphate (DNTP’s)

Question 2

What does attachment of DNTP’s require

Answer 2

removal of 2 phosphates (pyrophosphate)

Question 3

Which direction is DNA synthesized

Answer 3

5’ to 3’

Question 4

starting point of DNA replication

Answer 4

origin of replication

Question 5

what identifies starting point of replication

Answer 5

DnaA proteins

Question 6

what does dnaA do apart from identification

Answer 6

adds tension to H bonds to make them easier to break

Question 7

characteristic of the origin of replication

Answer 7

higher concentration of A and T (2 H bonds are easier to break)

Question 8

what does dnaB do

Answer 8

binds to starting point and pulls strands apart

Question 9

what helps dnaB to load onto the strands

Answer 9

dnaC

Question 10

energy source to pull strands apart

Answer 10

ATP hydrolysis

Question 11

What two things are required to keep the strands apart

Answer 11

single-strand binding proteins and topoisomerase

Question 12

Roll of topoisomerase in DNA replication

Answer 12

relieves supercoiling tension due to the strands being pulled apart

Question 13

When does DNA polymerase bind

Answer 13

when the strands are fully pulled apart

Question 14

what does DNA polymerase require to start

Answer 14

primer

Question 15

what adds the primer to the DNA strand

Answer 15

primase

Question 16

does the primer require

Answer 16

free 3’ OH group

Question 17

what is the primer

Answer 17

complimentary RNA based strand

Question 18

how fast does DNA polymerase work

Answer 18

1000 bases/s

Question 19

What does the proof reading during replication

Answer 19

exonuclease

Question 20

what direction is proof reading done in

Answer 20

3’ to 5’ (opposite to replication)

Question 21

what family of polymerase does bacteria use

Answer 21

family C

Question 22

which polymerase is involved in replication

Answer 22

polymerase III

Question 23

What are the two separated stands called

Answer 23

leading and lagging strands

Question 24

characteristics of leading strands

Answer 24

continuous

Question 25

characteristics of lagging strands

Answer 25

discontinuous, comprised of okazaki fragments, 1000-2000 bases

Question 26

DNA polymerase I function

Answer 26

removes RNA primers, also has 5' to 3' exonuclease activity

Question 27

what can DNA polymerase I not do

Answer 27

connect phosphodiester linkages

Question 28

function of DNA ligase

Answer 28

connects phosphodiester linkages

Question 29

characteristics of E. coli DNA replication

Answer 29

bidirectional from the replication fork

Question 30

how is DNA replication terminated

Answer 30

ter sites and Tus proteins forms blocker as replication forks come through

Question 31

function of blocker from ter sites and tus proteins

Answer 31

blocks polymerase from running into each other

Question 32

function of topoisomerase IV

Answer 32

unlinks chromosomes

Question 33

function of ftsK

Answer 33

separates chromosomes to poles

Question 34

what are plasmids

Answer 34

extrachromosomal pieces of DNA

Question 35

DNA characteristics of plasmids

Answer 35

double stranded, circular, found in prokaryotes, non essential for normal growth

Question 36

advantages of plasmids

Answer 36

adds antibiotic resistance genes, can add virulence factors

Question 37

how do plasmids replicate

Answer 37

rolling circle method

Question 38

characteristics of RNA

Answer 38

single stranded, ribose instead of deoxyribose, uracil instead of thymine

Question 39

how is transcription catalyzed

Answer 39

RNA polymerase

Question 40

basic characteristics of RNA polymerase

Answer 40

catalyzes the formation of phosphodiester bonds between ribonucleotide requires ribonucleoside triphosphates polymerizes in 5' to 3' direction requires a template has intrinsic helicase activity can initiate new strands of nucleotides on its own

Question 41

function of ribonucleoside triphosphates

Answer 41

energy from triphosphate

Question 42

template in RNA polymerase

Answer 42

DNA template

Question 43

what is required to initiate transcription

Answer 43

locating the promoter

Question 44

promoter in eukaryotes

Answer 44

TATA box

Question 45

what recognizes the promoter

Answer 45

transcription factors