Week 2 DNA mutation & molecular biology techniques

Question 1

What is mutation

Answer 1

Change in the genomic DNA

Question 2

What is the reason for mutation

Answer 2

Failure to repair DNA strand

Question 3

Consequences of Mutation

Answer 3

Loss or gain of function, dominant / negative effect

Question 4

Haploinsufficiency

Answer 4

Motor loss

Question 5

Gain of function explained

Answer 5

Chromosome rearranged, new function but may not respond to negative effects

Question 6

DNA glycosylase

Answer 6

Removes damaged base

Question 7

AP endonuclease

Answer 7

Identifies damaged location of strand

Question 8

DNA polymerase

Answer 8

Inserts new base to the strand

Question 9

DNA ligase

Answer 9

Seals the nick

Question 10

Base excision repair

Answer 10

Only repairs one strand

Question 11

Nucleotide excision repair mechanism enzymes

Answer 11

uvra,b,c,d and helicase 2 uvrD

Question 12

NER mechanism

Answer 12

uvrab scans for distortions/primer, the dna helix is distorted by dimer

uvrc and b bind together

uvr cleaves the bond 4-5 down, uvrc 8 nucleotides up

D removed this fragment

DNA polymerase adds nucleotide in 3-5D, DNA ligase finishes it

Question 13

Homologous recombination

Answer 13

Repairs a split in DNA strand

Question 14

HR mechanism

Answer 14

Broken strands create overhang

One of these strands invades a dna molecule to find complementary sequence

dna polymerase extends invading strand by using it as a template

Forms holiday junctions which allow for exchange of genetic material

Junction then cleaved by specific enzymes

Ligation completes this

Question 15

Stop codon

Answer 15

Sequence of nucleotides, shows the end of translation

Question 16

Missense mutation

Answer 16

AA replaced with another

Question 17

Frame shift

Answer 17

Add/del of nucleotide

Question 18

Silent mutation

Answer 18

Doesn’t affect AA being encoded

Question 19

What is electrophoersis?

Answer 19

Movement of a charged molecule in an electrical field

Question 20

The role of a pcr amplifier

Answer 20

To study a gene and to get many copies of it, to detect cancer, micro-organisms

Question 21

denaturation

Answer 21

Separating 2 strands of dna

Question 22

Restriction enzyme

Answer 22

recognises a particular set of sequences which then cuts them

Question 23

Maxam gilbert method

Answer 23

Cleaves dna strand at different bases use gel elctrophoerisis to separate strand to be then viewed

Question 24

Restriction enzyme

Answer 24

Recognises a particular sequence of dna and cuts it

Question 25

Variable number tandem repeats

Answer 25

location of genome where nucleotide sequence is repeated, found on chromosome