DNA Replication in Prokaryotes Flashcards Preview

IB HL biology > DNA Replication in Prokaryotes > Flashcards

Flashcards in DNA Replication in Prokaryotes Deck (20)
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1
Q

Function of DNA Helicase

A
  • unwinds the DNA at the replication fork
  • Breaks the hydrogen bonds between the bases
  • Requires ATP
2
Q

Function of DNA Gyrase

A
  • Removes the supercoiling created by the action of Helicase
3
Q

Function of DNA Polymerase III

A
  • Adds DEOXYNUCLEOSIDE TRIOSPHATES to the 3’ end
4
Q

Function of DNA Primase

A
  • Adds NUCELOSIDE TRIOSPHATES on the lagging strand to form an RNA primer
5
Q

Function of DNA Polymerase I

A
  • Removes RNA primer

- Replaces it using DEOXYNUCLEOSIDE TRIOSPHATES

6
Q

Function of DNA Ligase

A
  • Joins the Okazaki fragments together
7
Q

In what direction does DNA replication occur

A

5’ to 3’ direction

8
Q

What are Nucleosomes

A

Clumps of protein around which DN is coiled

9
Q

What are the functions of nucleosomes

A
  • supercoiling DNA

- Regulating transcription

10
Q

Which bases are pyramidines

A
  • Tymine
  • Cytosine
  • Uracil
11
Q

Which Bases are Purines

A
  • Adenine

- Guanine

12
Q

What are the 3 components of a nucleotide

A
  • Phosphate Group
  • Ribose Sugar in RNA
  • Deoxyribose sugar in DNA
  • Base (A,T/U,C,G)
13
Q

What does Antiparallel mean

A

The Two sugar-phosphate strands run in opposite directions

14
Q

What kind of bond link the sugar and the base/ phosphate and the base together

A

strong covalent

15
Q

what kind of bonds link the bases together

A

Hydrogen

16
Q

How many bonds are there between A and T

A

3

17
Q

How many bonds are there between C and G

A

2

18
Q

Why can replication only occur in 5’ to 3’ direction

A

polymerase enzymes can only add to the 3’ end of the strand

19
Q

what are the 3 types of DNA

A
  • protein coding DNA
  • non-protein coding DNA
  • non-coding DNA
20
Q

What id dideoxyribose

A

-Sugar that has no O and C3 and therefore prevents C5-C3 linkage