Lecture 1

Question 1

What does DNA compose of

Answer 1

Backbone made of sugar and phosphate groups.

Nitrogen containing bases that project from the backbone

Question 2

DNA

What gets exposed on the 3’ end carbon

Answer 2

Hydroxyl group

Question 3

DNA

What gets exposed on the 5’ end carbon

Answer 3

Phosphate group

Question 4

What is anti parallel fashion

Answer 4

Two DNA strands line up in the opposite direction to each other

Question 5

When antiparticle strands twist what does it make

Answer 5

Double helix

Question 6

How is the DNA structure stabilised

Answer 6

Complementary base pairs

Question 7

What base pairs bond to one another

Answer 7

Adenine - thymine

Guanine - cytosine

Question 8

Wha does the parent or original strand do

Answer 8

Serve as a template

Question 9

What happens in semi conservative replication

Answer 9

Parent strands seperate

Both used as a template for a new strand

Daughter molecules is made of one new and one old

Question 10

What happens in conservative replication

Answer 10

Parent strand serves as a template for synthesis of a whole new one

Question 11

What happens in dispersive replication

Answer 11

Parent strand is cut into sections

Daughter strand contains old DNA with new DNA

Question 12

What does DNA polymerase do

Answer 12

Enzyme that catalysed DNA synthesis

Question 13

What characteristic does the DNA polymerase have

Answer 13

It works in one direction

Question 14

What end does DNA polymerase add nucleotides too

Answer 14

3’ end

Question 15

How does replication start

Answer 15

Replication bubble

Question 16

What direction does the replication bubble work

Answer 16

Both as it is bidirectional

Question 17

What is the replication fork

Answer 17

Y shaped region where DNA is split into two seperate strands

Question 18

What does helicase do

Answer 18

Catalyses the breaking of hydrogen bonds between the two DNA strands to seperate them

Question 19

What do single strand DNA binding proteins do

Answer 19

Attach to the seperated strands to prevent them closing

Question 20

What does topi isomerise do

Answer 20

Cuts and rejoins the DNA and relieves the tension in the helix

Question 21

What does DNA polymerase require

Answer 21

Primer

Question 22

What is a primase

Answer 22

RNA polymerase

Question 23

What does RNA polymerase do

Answer 23

Synthesises a short RNA segment that acts as a primer

Question 24

What polymerase adds nucleotides after the RNA primer

Answer 24

DNA polymerase 3

Question 25

The two strands being used in replication what are they called

Answer 25

Leading strand

Continuous strand

Question 26

Which strand is synthesised discontinuous lu

Answer 26

Lagging strand

Question 27

When does the lagging strand start

Answer 27

Primase synthesises a short piece of RNA

Question 28

What are the short continuous fragments

Answer 28

Okazaki fragments

Question 29

What does DNA polymerase 1 do

Answer 29

Removes the RNA primer at the beginning of Okazaki fragments

Question 30

What does DNA Ligase do

Answer 30

Joins the Okazaki fragments together

Question 31

What is the replisome

Answer 31

Enzyme that is responsible for DNA synthesis aroud the replication fork

Question 32

What is a telomere

Answer 32

Region at the end of a linear chromosome

Does not contain genes

Question 33

After replication the lagging strand goes on a little longer than the template what happens to it

Answer 33

Gets degraded

Question 34

What cells lack telomerase

Answer 34

Somatic cells

Question 35

What does DNA polymerase 3 do

Answer 35

Proof read its work for any mismatched pairs

Question 36

During infection what happens to the protein coat

Answer 36

The original parent virus is left behind as a ghost attachment to the exterior cell