Bacterial DNA Replication & Recombination

Question 1

What are the 3 mechanisms used to explain DNA replication?

Answer 1

1. Conservative model
2. Semiconservative model
3. Dispersive model

Question 2

Existing DNA acts as a ________ for the synthesis of new strands

Answer 2

Template

Question 3

The __________ strand are the DNA strand that are used as a template to form the new DNA strand (which is called the daughter strand)

Answer 3

Parental

Question 4

Chargaff’s rule

Answer 4

States A binds to T & G binds to C

Question 5

Conservative model

Answer 5

Parental strands neanneal (produced)

Question 6

Semiconservative (hybrid)

Answer 6

1 parental & 1 daughter strand produced

Question 7

Dispersive

Answer 7

1 parental & daughter strand interspered

Question 8

DNA replication is _________________

Answer 8

Semiconserative

Question 9

Bacterial chromsomes contain a __________ origin of replication

Answer 9

Single

Question 10

Origin of replication

Answer 10

Site on the bacterial chromsomes where DNA synthesis begins (only have one)

Question 11

What are the requirments for bacterial replication?

Answer 11

1. Origin of replication
2. DNA polymerase
3. Accessory enzymes & topoisomerase

Question 12

The synthesis of new ___________ strand is initiated within the origin & proceeds in both directions (bidirectionslly) around the bacterial chromosome

Answer 12

Daughter

Question 13

A replication fork

Answer 13

The site where the parental DNA strand have seperated & a new daughter strand is being formed

Question 14

What are the 3 steps in bacterial DNA replication?

Answer 14

1. Initiation
2. Elongation
3. Termination

Question 15

Initiation

Answer 15

Bacteria has one origin of replication where it occurs bidirectionally

Question 16

Origin of replication in E. Coli is called ___________

Answer 16

OriC (Origin of chromosomeal replication)

Question 17

Bacterial DNA replication begins with the binding of __________ to sequence within the origin of replication known as DnaA boxes

Answer 17

DnaA proteins

Question 18

The ____________ served as recognition sites for the binding of the DnaA proteins where they bind to the five DnaA boxes in oric to start DNA replication

Answer 18

DnaA boxes

Question 19

Other DNA binding proteins bind to the DnaA boxes to seperate _________ rich regions since they have only 2 hydrogen bonds & G-C has 3 hydrogen bonds so they can easily seperate A-T

Answer 19

A-T regions

Question 20

______________ unwinds the DNA strand by breaking the A-T bond which can cause a supercoling

Answer 20

DNA helicase

Question 21

DNA replication occurs at the _____________

Answer 21

Replication fork

Question 22

___________________ travels in front of the DNA helicase to release the supercoling

Answer 22

Topoisomerase 2

Question 23

Single strand binding proteins

Answer 23

Bind to the strands of parental DNA & prevents them from reforming after being seperated by DNA helicase

Question 24

After the bonds between the nucleotides are broken a ________ forms RNA primers where the RNA primers starts the DNA replication

Answer 24

Primase

Question 25

The leading stramd

Answer 25

Made in the same direction as the replication fork is moving

Question 26

The lagging strand

Answer 26

Short fragments in the opposite direction from the movement of the replication fork

Question 27

The DNA helicase moves in the ___________ direction & seperates the DNA strand in two directiion creating 2 replication forks

Answer 27

5' to 3' direction

Question 28

DNA polymerase

Answer 28

Synthesizes the new DNA strand (both the lagging & leading strand )

Question 29

DNA polymerase travels unidirectional in the 3' to 5' direction but makes new strand in the _________ direction which is antiparallel to the template strand & forms a daughter strand DNA (or new DNA)

Answer 29

5' to 3' direction

Question 30

A _____________ starts the replication process & DNA polymerase actually makes the new DNA strand

Answer 30

RNA primer

Question 31

What are the 5 types of DNA polymerase?

Answer 31

1. Polyermase 1 2. Polyermase 2 3. Polyermase 3 4. Polyermase 4 5. Polyermase 5

Question 32

DNA polyermase ___ & _____ are used in normal DNA replication

Answer 32

1 & 3 (Mostly 3 though)

Question 33

DNA polymerase \_\_\_, \_\_\_\_\_, & _____ used in DNA repair

Answer 33

2, 4, & 5

Question 34

Polymerase is undirectional & only travels in the _____________ direction

Answer 34

5' to 3' direction

Question 35

The synthesis of the leading strand is ___________ whereas the synthesis of the lagging strand is ___________ process where it repeatedely needs to start

Answer 35

Continous, discontinous

Question 36

The lagging strands are known as what?

Answer 36

Okazaki Fragments

Question 37

\_\_\_\_\_\_\_\_\_\_\_\_ degrades the primer & fills in the gaps between the lagging strand

Answer 37

Polymerase 1

Question 38

\_\_\_\_\_\_\_ links the okazaki fragments together

Answer 38

Lingase

Question 39

\_\_\_\_\_\_\_\_\_\_\_\_\_ removes the RNA from okazaki fragments (nuclease activity) (Polymerase activity forming DNA nucleotides the daughter strand)

Answer 39

Polyermase 1

Question 40

Each replication fork has a _______ & _______ strand

Answer 40

Leading & lagging strand

Question 41

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ removes the RNA primers & fills it with DNA nucleotides

Answer 41

Polyermase 1

Question 42

Elongation

Answer 42

Leading & lagging strand elongate (due to polymerase 3)

Question 43

\_\_\_\_\_\_\_\_\_\_\_ is more complex than bacterial DNA replication where the chromosomes are larger, linear, longer, & highly packed

Answer 43

Eukaryotic replication

Question 44

\_\_\_\_\_\_\_\_\_\_ replication has multiple origin of replication (Initiation occurs at multiple origins of replication on linear eukaryotic chromosome)

Answer 44

Eukaryotic DNA replication

Question 45

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ can't replicate ends of DNA genetic material is lost, it makes a new DNA in the 5' to 3' direction but can't start the replication process (Because no place for a primer to bind & polymerase needs a primer to start)

Answer 45

DNA polymerase

Question 46

\_\_\_\_\_\_\_\_\_\_\_\_ are repetitive sequences at the end of chromosomes that are 3' overhang

Answer 46

Telomers

Question 47

\_\_\_\_\_\_\_\_\_\_\_\_\_ enzyme replicates telomers to maintain the length of a chromosome, it has proteins & RNA where the RNA is complementary to telomerase sequence

Answer 47

Telomerase

Question 48

\_\_\_\_\_\_\_\_\_\_\_\_ makes 6 new nucleotides on the RNA template & the new nucleotides make a bind site for the primase to make the RNA primer

Answer 48

Telomerase

Question 49

\_\_\_\_\_\_\_\_\_\_\_ extends telomers

Answer 49

Telomerase

Question 50

The ends of eukaryotic chromosomes are replicated by \_\_\_\_\_\_\_\_\_

Answer 50

Telomerase

Question 51

\_\_\_\_\_\_\_\_\_\_\_ prevents chromosome shortening

Answer 51

Telomerase

Question 52

\_\_\_\_\_\_\_\_\_\_ can cause stress which causes shorter telomeres (which is bad for our health)

Answer 52

Children