Manipulating genomes

Question 1

DNA profiling steps

Answer 1

• extraction and PCR
• DNA cut by restriction endonucleases
• seperating via gel electrophoresis
• alkali solution used to seperate strands
• southern blotting, transfer from gel to nylon membrane
• hybridisation- florescent or radioactive tags added
• seeing - either x ray or UV light used

Question 2

hybridization

Answer 2

radioactive tags or florescent tags added
- radioactive show up under x ray
- florescent show up under UV light

Question 3

Restriction endonucleases

Answer 3

-specific to a nucleotide sequence
- all restriction endonucleases make 2 cuts

Question 4

restriction endonucleases make cuts at

Answer 4

recognition sites/ restriction sites

Question 5

Microsatellites vs minisatellites

Answer 5

short, tandemly repeated DNA

Question 6

Tandem repeats in DNA

Answer 6

like ACACAC
or
GACGACGAC
A short section of bases repeated

Question 7

where can tandem repeats be found

Answer 7

inside introns

Question 8

minisatellite other name and what is it

Answer 8

Variable tandem repeats- lots of base pairs repeated more times

Question 9

Microsatellites other name and what is it

Answer 9

short tandem repeats, short base sequences repated less times

Question 10

PCR process

Answer 10

• 95° Hydrogen bonds between fragments of DNA Broken
• 55° DNA primers anneal.
• 72° Adds bases to primer, TAQ polymerase used. double strand formed

Question 11

uses of DNA profiling (3)

Answer 11

• crime scenes
• paternity tests
• individuals at risk of developing particular diseases

Question 12

DNA sequenceing vs DNA profiling

Answer 12

sequencing identifies specific sequence of bases - profiling identifies specific regions of DNA

Question 13

equipment used for PCR

Answer 13

thermal cycler

Question 14

Fredrick sanger technique

Answer 14

• carried out manually
• radioactive labelling of bases

Question 15

DNA sequencing

Answer 15

• DNA mixed primer, Taq polymerase, nucleotides and terminator bases.
• mixture put in thermal cycler PCR occurs
• a terminator base is incorperated instead of a normal base.
• results in fragments of many different lengths.
• all the possible DNA lenths will be produced
• gel electrophoresis via capillary sequencing
• lasers detect florescent tags on terminator bases.

Question 16

Terminator bases can’t

Answer 16

for phosphodiester bonding

Question 17

capilliary sequencing

Answer 17

• separating fragments based on size
• minute capilliary tubes

Question 18

Computational biology

Answer 18

• data tobuild theoretical models of biological systems
• used for predictions of 3D structures of protien

Question 19

bioinformatics

Answer 19

analyse raw data, develop algorithms

Question 20

why might scientists analyse the genomes of pathogens?

Answer 20

• to find source of infections
• identifying antibiotic resistant strains of bacteria
• track progress of an outbreak
• identify regions of the genome that may be useful targets for drugs.

Question 21

in comparative biochemistry, what gene is used in animals

Answer 21

mitochondrial gene for cytochrome C oxidase

Question 22

evolutionary relstionships can be found by…

Answer 22

• comparing rate of base mutations to the sequences if different organisms. calculating how long ago the two species diverged

Question 23

proteomics

Answer 23

study of all the amino acids produced by an organism. it is interesting that some genes code for many amino acids.

Question 24

spliceosomes

Answer 24

enzyme complexes that join together exons after splicing

Question 25

synthetic biology

Answer 25

design and construction of novel synthetic pathways

Question 26

techniques in synthetic biology (4)

Answer 26

- creating new organisms - genetic engineering - biological systems in industrial context (immobalised enzymes) - synthesis of new genes to replace faulty ones

Question 27

steps to creating recombinant DNA

Answer 27

- plasmid removed from bacteria - mRNA from desired gene - reverse transcriptase creates complementary DNA (cDNA) - restriction endonucleases used to cut a specific pallendromic sequence in both bacterial plasmid and cDNA. sticky ends formed. - DNA ligase used to form phosphodiester bonds between sticky ends - electroporation used to reintroduce recombinant plasmid to bacterial cell

Question 28

explain electroporation

Answer 28

small electrical current used to make membrane porous and reintroduce plasmid

Question 29

explain electrofusion

Answer 29

electric currents used to fuse membranes of two cells together creating polyploid cell w two sets of DNA (ploid is a root that means sets of chromosomes)

Question 30

ways of telling if plasmid has taken up gene

Answer 30

- florescent genes that get removed if recombination is successful - genes that cause bacterial resistance are removed if recombination is successful

Question 31

electrofusion is used in...

Answer 31

plants

Question 32

examples of GM animals

Answer 32

- faster growing salmon - swine fever resistant pigs

Question 33

pharming

Answer 33

genetic engineering in animals to produce human medicines

Question 34

pharming techniques

Answer 34

- creating human protiens - creating animal models for development of new therapies

Question 35

knockout mice

Answer 35

have had certain genes "knocked out". gives indication of function of knocked out gene

Question 36

somatic cell gene therapy

Answer 36

replaces mutant allele with healthy allele in body cells.

Question 37

germ line gene therapy

Answer 37

healthy allele replaces mutant allele in germ cells (egg or sperm cell)