gene technology

Question 1

recombinant DNA technology

Answer 1

combining different organisms DNA
enable scientist to manipulate and alter genes to improve industrial processes and medical treatment

Question 2

sequencing projects

Answer 2

reading the full genome of organisms
provides opportunity to screen DNA to identify potential medical problems

Question 3

how can you create a DNA fragment

Answer 3

reverse transcription with reverse transcriptase
restriction endonucleases
gene machine

Question 4

gene machine

Answer 4

creates DNA fragments using a computerised machine

Question 5

reverse transcriptase

Answer 5

An enzyme that makes a cDNA single-stranded copies of DNA from mRNA

Question 6

restriction endonucleases

Answer 6

enzymes that cut up DNA to create fragments
cut at specific recognition/ restriction sequence
results in sticky ends

Question 7

in vivo cloning

Answer 7

creating DNA fragments using bacteria
involves restriction endonuclease enzymes

Question 8

in vitro cloning

Answer 8

using PCR to create a large number of copies of a DNA fragment

Question 9

uses of PCR

Answer 9

used widely in gene technology to make large numbers of copies of DNA fragments

Question 10

describe the process of PCR

Answer 10

increase temperature to 95C to
break hydrogen bonds & split
DNA into single strands
temperature is decreased to 55C
so primers can attach
DNA polymerase joins
complementary nucleotides &
makes a new strand
temperature increased to 72C
(optimum for Taq DNA
polymerase

Question 11

uses of genetic fingerprinting

Answer 11

Forensic science
medical diagnosis
plant/animal breeding
paternity tests

Question 12

what is gel electrophoresis

Answer 12

separation of DNA samples using an electrial voltage
different lengths of DNA VNTRs are separated

Question 13

why does the DNA move in gel electrophoresis

Answer 13

DNA is negatively charged and
moves towards the positive end
of the gel
the shorter the piece of DNA, the
faster and further it moves

Question 14

what is genetic screening

Answer 14

testing DNA to identify the presence of alleles that can cause/ increase the risk of developing a disease

Question 15

what is genetic counselling

Answer 15

a type of social work giving people advice and information following the screening of disease causing alleles

Question 16

what is cDNA

Answer 16

complementary, single-stranded DNA strands
created by reverse transcriptase

Question 17

what are the advantages of using the gene machine

Answer 17

very quick
accurate
create intron-free DNA

Question 18

what are the advantages of using reverse transcription

Answer 18

creates intron-free cDNA

Question 19

what are the advantages using restriction endonucleases

Answer 19

creates sticky ends on DNA to enable the DNA fragments to join with complementary base pairs

Question 20

oligonucleotides

Answer 20

shorts DNA molecules
used in gene machine to create DNA fragments

Question 21

sticky ends

Answer 21

exposed staggered ends of bases
palindromic base sequences created by restriction enzymes

Question 22

palindromic sequence

Answer 22

sequences of bases that read the same forwards as they do backwards

Question 23

blunt end

Answer 23

When a restriction enzyme cuts the DNA double-strand in the same position
There is no overhang of bases

Question 24

what are the two methods to amplify DNA

Answer 24

in vivo
in vitro

Question 25

promoter region

Answer 25

a sequence of DNA that is binding site for RNA polymerase to enable transcription to occur

Question 26

terminator region

Answer 26

added at the end of the gene It causes RNA polymerase to detach and stop transcription to ensure one gene is copied into mRNA at a time

Question 27

plasmid

Answer 27

a small loop of bacterial DNA contain only a few genes contains the genes for antibiotic resistance

Question 28

recombinant plasmid

Answer 28

a small loop of bacterial DNA with the DNA from another organism inserted into it

Question 29

transformation

Answer 29

The process of getting a plasmid to re-enter a bacterium involves calcium ions and temperature shocking

Question 30

how can transformed cells be identified

Answer 30

using marker genes antibiotic resistance genes genes coding for fluorescent proteins genes coding for enzymes

Question 31

what is a marker gene

Answer 31

genes on the plasmid used to identify which bacteria successfully took up the recombinant plasmid

Question 32

DNA probe

Answer 32

short, single-stranded pieces of DNA labelled radioactively or fluorescently so that they can be identified

Question 33

DNA hybridisation

Answer 33

DNA is heated to separate the double helix into single strands its then mixed with complementary sequences of single-stranded DNA it's then cooled so complementary strands will anneal

Question 34

personalised medicine

Answer 34

screening for the presence of particular alleles to select medicines and personalise health advice based on your genotype

Question 35

VNTRs

Answer 35

variable number tandem repeats sequences of bases in introns unique to each person

Question 36

How can DNA samples be collected

Answer 36

from blood, body cells or hair follicles

Question 37

how is DNA extracted from cells so that it can be examined

Answer 37

cell fractionation and ultracentrifugation

Question 38

how is DNA digested in genetic fingerprinting

Answer 38

Restriction endonucleases are added to cut the DNA into smaller fragments enzymes that cut close to the target VNTRs are added

Question 39

Why can the genome not be easily translated into the proteome in complex organisms

Answer 39

due to the presence of non-coding DNA and regulatory genes

Question 40

what is the role of DNA ligase in making recombinant DNA

Answer 40

used to stick the DNA fragment to create recombinant DNA