DNA Replication

Question 1

DNA replication is _______

Answer 1

Semiconservative

Question 2

DNA is shaped like a ____ _____ (twisted ladder)

Answer 2

double helix

Question 3

The backbone of the two strands of the ladder contain?

Answer 3

Sugar and phosphate groups

Question 4

Rungs of the ladder contain?

Answer 4

Nitrogenous Bases

Question 5

The “rungs” of the ladder are connected as ____ ____ between the nitrogenous base of one strand and the nitrogenous base of the other strand

Answer 5

base pairs

Question 6

DNA Base Pairs:

The bases are connected by?

Answer 6

hydrogen bonds

Question 7

What are the four base pairs of DNA?

Answer 7

-Adenine (A)
-Thymine (T)
-Guanine (G)
-Cytosine (C)

Question 8

Adenine and Thymine are formed by ___ hydrogen bonds?

Answer 8

2

Question 9

Guanine and Cytosine are formed by ___ hydrogen bonds

Answer 9

3

Question 10

One end of each chain the 5 carbon with the phosphate group is “closed”

Answer 10

5’ end

Question 11

One end of each chain the 3 carbon with an -OH group is “open”

Answer 11

3’ end

Question 12

DNA:
Strands run in opposite directions

Answer 12

antiparallel

Question 13

Original Strand
5’ ATCGCTG 3’
Complimentary strand?

Answer 13

3’ TAGCGAC 5’

Question 14

Crick’s Central Dogma:

Genetic information is stored in ______ and transferred to _______

Answer 14

DNA, Protein

Question 15

Crick’s Central Dogma:

Transfer of information to proteins is _______

Answer 15

irreversible

Question 16

Watson & Crick Replication:

The ______ unwinds

Answer 16

helix

Question 17

Watson & Crick Replication:

Both strands are intact

Answer 17

parental strands

Question 18

Watson & Crick Replication:

Each parent strand serves as a template for a new ____ _____

Answer 18

daughter strand

Question 19

Watson & Crick Replication:

Daughter strands are generated by ______ ______ ______ to the parental strand

Answer 19

complementary base pairing

Question 20

DNA Replication: Prokaryote

-One piece of circular DNA
-4.6 million base pairs
-Copied in as little as 20 minutes

Answer 20

E.coli

Question 21

DNA Replication: Eukaryote

-46 chromosomes
-6.4 billion base pairs
-copied in a few hours

Answer 21

Homo sapiens (humans)

Question 22

DNA Replication 3 basic steps?

Answer 22

-Initiation
-Elongation
-Termination

Question 23

DNA Replication Steps:

-Proteins bind to a specific location
-origin of replication
-Requires single stranded DNA

Answer 23

Initiation

Question 24

-Unwinds the helix at the replication fork
-Necessary to generate the single-stranded template strands

Answer 24

Helicase

Question 25

-Binds and stabilizes the single-stranded templates -Prevents helix from rewinding

Answer 25

Single-Strand Binding Proteins (SSBP)

Question 26

-Causes single-strand breaks that allow the DNA to unwind and relieve the supercoil strain -The breaks are resealed before replication -Relaxes supercoils

Answer 26

Topoisomerase

Question 27

DNA Replication Steps: DNA polymerase binds the nucleotide to the 3' end of the daughter strand

Answer 27

Elongating

Question 28

Add nucleotides only into -OH of a free 3' end; ______ onto to the 5' end

Answer 28

NEVER

Question 29

If there is no available free 3' end, then complementary nucleotide _______ is generated

Answer 29

primer

Question 30

Primer is a short piece of ______ with a free -OH at the 3' end

Answer 30

RNA

Question 31

RNA primers are needed to initiate ______ new DNA strands

Answer 31

all

Question 32

Priming DNA Synthesis: Synthesized by ____

Answer 32

Primase

Question 33

RNA Primase doesn't need a _____ to start

Answer 33

3' end

Question 34

Linear DNA elongates in the ___ ---> _____ direction only

Answer 34

5' ---> 3'

Question 35

Direction of synthesis is _____ the fork and _____ from the origin

Answer 35

toward, away

Question 36

-Short discontinuous fragments -Each fragment needs a separate RNA primer -The primer is eventually removed, and new DNA fills the space

Answer 36

Okazaki Fragments

Question 37

DNA strands synthesized discontinuously are called?

Answer 37

lagging strands

Question 38

Replication errors are

Answer 38

Mutations

Question 39

can recognize and replace an incorrect nucleotide as it synthesize the daughter strand

Answer 39

DNA polymerase III

Question 40

Continuously synthesized strand

Answer 40

Leading strand

Question 41

The enzyme that removes RNA primers and fills in the gaps with DNA is called

Answer 41

DNA Polymerase I

Question 42

Enzyme that seals the gaps between Okazaki fragments on the lagging strand is called

Answer 42

DNA ligase

Question 43

Leading strand direction

Answer 43

5’ —->3’

Question 44

Lagging strand direction

Answer 44

3’ —-> 5’

Question 45

Synthesizes RNA primers with a 3’ end for a new strand

Answer 45

Primase

Question 46

Okazaki strands go in what direction

Answer 46

5' --> 3'

Question 47

-Adds nucleotides to the 3’ end of the daughter strand -Proof reads and repairs mismatched DNA

Answer 47

DNA polymerase

Question 48

Joins DNA fragments together by forming bonds, seals

Answer 48

Ligase