Bi 140 Patterns Of Inheritance 29

Front 1

Initiation

Back 1

Step One:
-DNA gyrase uncoils DNA molecule
-Initiation occurs at specific site called oriC region which is rich in A's and T's which is easier to uncoil because they have double bonds not triple bonds
Step Two:
-Initiator proteins (SSBP) binds to DNA strand and stabilizes
Step Three: Helicase unzips ds DNA by breaking H bonds

Front 2

Elongation

Back 2

Step 4:
-Primase adds a 10-20 base pair piece (primer) of RNA to end of each ss DNA molecule
-Multiple primers added to LAGGING strand
-DNA replication occurs in 5' to 3' direction (3'---5' leading, 5'---3' lagging)
Step 5: LEADING
-DNA pol III binds to DNA at fork
-Clamp and clamp loader lock enzyme onto DNA
-DNA pol III slides down DNA strand toward 5' end adding nucleotides to complementary bases on template
-H-bonds form between bases and phosphodiester bonds between sugars to make ds back bone
Step 5: LAGGING
-DNA pol III attaches to DNA and is clamped
Step 6:
-DNA pol III synthesizes Okazaki fragments
-At end of each fragment it is released and reattaches to beginning of each fragment
(5-->3 , 3<---5 harder) Synthesized in Okazaki fragments

Front 3

Termination

Back 3

Step 7: DNA polymerase I removes primers, fills in gaps between fragments on lagging strand so have a complete strand
Step 8: DNA ligase connects all pieces together

Front 4

DNA gyrase

Back 4

Relieves torque

Front 5

Helicase

Back 5

Unwinds the double helix by breaking H-bonds

Front 6

SSBP

Back 6

initiator proteins

Front 7

Primase

Back 7

Synthesizes RNA primers

Front 8

DNA polymerase III

Back 8

Synthesizes DNA

Front 9

Clamp and Clamp loader

Back 9

The beta subunit is made up of two identical protein chains that come together to form a circle, this circle can be loaded onto the template like a clamp.
Multisubunit protein called clamp loader accomplishes opening and closing the clamp around the DNA

Front 10

DNA polymerase I

Back 10

Erases primer and fills gaps

Front 11

DNA ligase

Back 11

Joins the ends of DNA segments; DNA repair

Front 12

E. Coli

Back 12

-DNA is 1000x longer than cell
-30 miles fishing line into a blueberry
-Supercoiling: twisted and packed to fit

Front 13

oriC

Back 13

site where initiation occurs

Front 14

supercoiling

Back 14

twisting and packing DNA to fit into a cell

Front 15

Initiator proteins

Back 15

(SSBP) binds to DNA strand and stabilizes

Front 16

Replication fork

Back 16

The opening between two strands

Front 17

Primer

Back 17

10-20 base pair piece of RNA added to each end of ss DNA molecule

Front 18

Antiparallel

Back 18

3'--5'
5'--3'

Front 19

Discontinuous

Back 19

The lagging strand

Front 20

Lagging strand

Back 20

-Discontinuous

Front 21

Leading strand

Back 21

Continuous

Front 22

Okazaki fragments

Back 22

DNA fragments synthesized on the lagging strand. They introduce a need for even more enzymatic activity on lagging strand

Front 23

What are the 3 main events in DNA replication?

Back 23

Initiation
Elongation
Termination

Front 24

What enzymes are required for DNA replication?

Back 24

Helicase, primase, SSBP, DNA gyrase, DNA pol III, DNA pol I, DNA ligase

Front 25

template

Back 25

The parental DNA strand serves as the template to be copied by the enzymes

Front 26

replisome

Back 26

Enzymes involved in DNA replication forms macromolecular assembly called the replisome.
-Replication organelle
-Contains all necessary enzymes for replication

Front 27

What is supercoiling and why is it needed?

Back 27

Supercoiling is the twisting and packing of DNA to fit within a cell

Front 28

What chemical bonds are formed during elongation?

Back 28

During elongation, Hydrogen bonds are formed between bases (double between A and T, triple between C and G) and phosphodiester bonds form between the sugars to make the ds backbone