Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology A2 Rafa > 6.3 Manipulating Genomes > Flashcards

6.3 Manipulating Genomes Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

Define polymerase chain reaction

A

A biomedical technology in molecular biology that can amplify a short length of DNA to thousands of millions of copies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Applications of PCR

A 
Tissue typing
Detection of oncogenes
Detecting mutations 
Identifying viral infections
Monitoring the spread of infectious disease
Forensic science
Research
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Applications of PCR

A 
Tissue typing
Detection of oncogenes
Detecting mutations 
Identifying viral infections
Monitoring the spread of infectious disease
Forensic science
Research
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Define DNA ligase

A

Enzymes that catalyses the joining of sugar and phosphate groups writhing DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Define electroporation

A

Method for introducing a vector with a novel gene into a cell; a pulse of electricity makes the recipient cell membrane more porous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Define plasmids

A

Small loops of DNA in prokaryotic cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Define recombinant DNA

A

A composite DNA molecule created in vitro by joining foreign DNA with a vector molecule such as a plasmid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Define restriction enzymes

A

Endonuclease enzymes that cleave DNA molecules at recognition sites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Define vector

A

In gene technology, anything that can carry/ insert DNA into a host organism; examples of such vectors include plasmids, viruses and certain bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Necessary stages of genetic engineering

A
  • required gene is obtained
  • copy of the gene is placed inside a vector
  • vector carries gene to recipient cell
  • the recipient expresses the novel gene
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is DNA sequencing?

A

A technique that allows genes to be isolated and read

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Who developed the technique that allows you to sequence whole genomes?

A

Fred Sanger

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What was sangers approach?

A

Use a single strand of DNA as a template for four experiments in different dishes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What was in each one of Sanger’s dishes?

A

Solution with four bases and DNA polymerase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What did Sanger add to each tube?

A

Modified version of one of the DNA bases that meant once it was added to complementary DNA, no more bases could be added

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is each base labelled with in Sanger’s experiment?

A

Radioactive isotope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

In gel electrophoresis, which fragments travel the furthest?

A

Smaller ones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What were the terminal bases labelled with in the first DNA sequencing machine?

A

Fluorescent dyes which glowed when scanned with a laser beam

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What does pyrosequencing involve?

A

Synthesising a single strand of DNA, complementary to the one being sequences, one base at a time whilst detecting by light emission which base was added at each step

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Steps of pyrosequencing

A

-DNA is cut into 300-800 base fragments using a nebuliser
-fragments degraded to single stranded DNA
-they are immobilised
-primer added and DNA incubated with enzymes
-activated nucleotides added and
light detected

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

In pyrosequencing, what enzymes is the DNA incubated with?

A

DNA polymerase, ATP sulfurylase, luciferase, apyrase and the substrates adenosine 5’ phosphosulfate (APS) and luciferin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What activated nucleotides are used in pyrosequencing?

A

ATP
TTP
CTP
GTP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What happens when an activated nucleotide is added in pyrosequencing?

A
  • Two extra phosphoryls are released as pyrophosphate (PPi)
  • The enzyme ATP sulfurylase converts pyrophosphate to ATP by combining it with APS
  • ATP and luciferin are converted to oxyluciferin by luciferase
  • this generates light
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are unincorporated nucleotides degraded by?

A

Apyrase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the applications of gene sequencing?

A
  • genome wide comparisons between individuals
  • genome wide comparisons between species
  • sequences of amino acids in polypeptides to be predicted
  • development of synthetic biology
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Examples of synthetic biology applications?

A 
Information storage
Production of medicines
Novel proteins
Biosensors
Nanotechnology
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Examples of nanotechnology

A

Amyloid fibres making biofilms

For functions such as adhesion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Basic stages of DNA profiling

A

Extract sample of DNA
DNA digested with restriction enzymes, which cut into fragments
Fragments separated by gel electrophoresis and stained
Banding pattern
Compare with other DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Why is restriction fragment length polymorphism analysis no longer used?

A

Laborious

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What types of DNA are analysed in DNA profiling?

A

Short tandem repeat (STR) sequences of DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

How many STRs are analysed simultaneously?

A

13

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Applications of DNA profiling

A

Forensic science
Maternity and paternity disputes
Analysis of disease
Plant and animal breeding (reduces inbreeding)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

How has profiling been used in forensic science?

A

Identifying nazi war criminals in South America
Identify remains of Romanov family
Victims bodies in disasters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

How much of STR repeats come from mother and father?

A

Half from mother half from father

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Example of how DNA profiling is used in disease analysis

A
  • detect haemoglobin present and aid diagnosis of sickle cell anaemia
  • Huntington’s repeat sequence number
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is PCR?

A

A biomedical technology in molecular biology that can amplify a short length of DNA to thousands of millions of copies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What does PCR do?

A

Amplify amount of DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What facts does PCR rely on?

A
  • DNA is anti parallel
  • have 5’ and 3’ end
  • DNA only grows from 3’ end
  • complementary bases pair up
39
Q

How does PCR differ from DNA replication?

A

Short sequence replicated, not chromosomes
Requires primer molecules
Cycle of heating and cooling need to separate DNA strands, bind primers to strands and for strands to be replicated

40
Q

What type of reaction is PCR?

A

Cyclic

41
Q

Why was the process of PCR slow at first and how was it sped up?

A
  • DNA was heated to denature it and then cooled to 35 degreees to anneal primers and allow polymerase to work
  • DNA polymerase was obtained from Thermophilus aquaticus, thermophilic bacterium
  • Taq polymerase is stable at high temperatures
42
Q

Applications of PCR?

A
  • tissue typing
  • detection of oncogenes
  • detecting mutations
  • identifying viral infections
  • ANALYSIS OF DISEASE RISK
  • FORENSICS
  • research
  • to produce enough DNA to mix with cut plasmids to insert into bacteria (in vivo cloning)
43
Q

What is tissue typing?

A

Donor and recipient tissues typed before transplantation to reduce risk of rejection

44
Q

What viral infections can PCR identify?

A

HIV or hepatitis C

45
Q

What’s the sample of DNA mixed with in PCR to start? + Where is this mixture put?

A 
DNA nucleotides
Primers
Magnesium ions
Taq DNA polymerase 
-All in thermocycler
46
Q

What is the DNA heated to the first time in PCR and why?

A

94-96 degrees
To break H bonds between complementary nucleotide bases
Two single strands of DNA

47
Q

What is the PCR mixture cooled to and why and what is produced?

A

68 degrees
Primers can anneal to one end of each single strand of DNA
A small section of double stranded DNA at the end of each single stranded molecule

48
Q

What is the optimum temp for Taq polymerase?

A

72 degrees and the mixture is raised to this

49
Q

What does Taq polymerase do?

A

Catalyses the added of nucleotides to single stranded DNA
Start at the end with primer
5’ to 3’

50
Q

How does the amount of DNA increase in PCR?

A

Exponentially

1-2-4-8-16-32-64-128

51
Q

After running gel electrophoresis on your DNA sequence what do you expose it to?

A

Photographic paper due to the radioactive isotopes

52
Q

Name of sequences forensic DNA tests use to identify individuals

A

Variable number tandem repeats

53
Q

Advantages of PCR?

A
  • rapid

- no living things involved

54
Q

Disadvantages of PCR?

A

Contaminant DNA may also be amplified

55
Q

What is electrophoresis?

A

process used to separate proteins or DNA fragments of different sizes

56
Q

What does electrophoresis use?

A

Agarose gel plate covered by a buffer solution

Electrodes at each end

57
Q

What is the overall charge of DNA and why?

A

Negative due to its many phosphate groups

58
Q

Which way do DNA fragments move in gel electrophoresis?

A

Towards the positive electrode (anode)

59
Q

Why are the samples in electrophoresis only separated by size?

A

Because different size fragments of DNA all have a similar surface charge

60
Q

Which fragments of DNA move the furthest in gel electrophoresis?

A

The shortest ones

61
Q

Difference between electrophoresis of proteins and electrophoresis of DNA?

A

-proteins = often carried out in the presence of a charged detergent such as sodium dodecyl sulfate (SDS) which equalises surface charge

62
Q

Why do we need SDS in protein electrophoresis?

A

Because proteins may have different surface charge

63
Q

What can gel electrophoresis of proteins be used to analyse?

A

types of haemoglobin for:

  • sickle cell anaemia
  • aplastic anaemia, thalassaemia and leukaemia
64
Q

What are DNA probes?

A

Small bits of DNA which know sequences
single stranded
tagges

65
Q

What can DNA probes be labelled using?

A
  • radioactive marker

- fluorescent marker (emits colour change on exposure to UV light)

66
Q

What can we use DNA probes for?

A
  • locating a gene to be used in genetic engineering
  • genome comparison studies
  • identifying alleles for genetic disease
67
Q

What is a DNA microarray?

A

A number of different probes on a fixed surface

68
Q

How do microarrays work?

A

You put your sample of DNA onto the plate with the probes and scan it

  • probes may be flourescently labelled and fluoresced when hybridised to samples of added DNA
  • tell you which probes were successful in detecting complementary sequences
  • can infer which sequences of DNA were in samples
69
Q

Use of microarrays and electrophoresis

A
  • locating and identifying alleles
  • genetic screening
  • personalised medicine
  • genetic counselling
70
Q

Define DNA ligase

A

enzyme that catalyses the joining of sugar and phosphate groups within DNA

71
Q

What is electroporation?

A

method for introducinga vector with a novel gene into a cell; a pulse of electricity makes the recipient cell more porous

72
Q

What are plasmids?

A

small loops of DNA in prokaryotic cells

73
Q

What is recombiant DNA?

A

a composite DNA molecule created in vitro by joining foreign DNA with vector molecule such as a plasmid

74
Q

What are restriction enzymes?

A

endonuclease enzymes that cleave DNA molecules at specific recognition sites

75
Q

What is a vector?

A

in gene technology, anything that can carry/insert DNA into a host organism; examples of such vectors include plasmids, viruses and certain bacteria

76
Q

Necessary stages of genetic engineering

A
  • required gene obtained
  • copy placed into vector
  • vector carried gene into recipient cell
  • recipient expresses the novel gene
77
Q

Methods for obtaining required gene in genetic engineering

A
  • mRNA obtained, reverse transcriptase makes a single strand of complementary DNA (cDNA) with the addition of primers and DNA polymerase can make double stranded
  • automated polynucleotide synthesiser (if you know whole sequence)
  • PCR to amplify known gene
  • DNA probe locates gene and cut out using restriction enzymes
78
Q

How can you place a gene into a vector?

A
  • plasmids obtained from microorganisms and mix with restriction enzymes that cut plasmid at specific recognition sites
  • the plasmid now has exposed unpaired nucleotide bases, sticky ends
  • free nucleotide bases that match are added to the gene bing inserted and DNA ligase catalyses the annealing of the gene into plasmid
  • gene may be seal into a weakened virus that could carry it into a host cell
79
Q

Methods of putting vector into recipient cell

A

-heat shock treatment
-electroporation
-electrofusion
-transfection
T1 (recombinant) plasmids inserted into bacterium, Agrobacterium tumefaciens, which naturally inserts
-gene gun

80
Q

What is heat shock treatment?

A

bacteria subjects to alternating 0-42 degrees in the presence of calcium chloride
membranes become more porous, DNA can enter

81
Q

What is electroporation?

A

high voltage pulse disrupts membrane

82
Q

What is electrofusion?

A

electrical fields help introduce DNA into cells

83
Q

What is transfection?

A

DNA packaged into bacteriophage

transfects host cell

84
Q

What are direct methods of introducing genes into recipient?

A

If plants are not susceptible to A.tumefaciens
small pieces of gold or tungsten coated with DNA and shot into plant cells
GENE GUN

85
Q

Ethical considerations of genetic engineering?

A
  • escape of resistance genes (into weeds, eg herbicide resistance)
  • health and welfare of GM animals (testing)
86
Q

Positive of GM soya

A

resistant to herbicides

weeds competing with soya plants can be killed using herbicides

87
Q

Negative of GM soya

A

herbicide resistance pass into weeds producing superweeds

88
Q

Positive of GM pathogens

A
  • viruses, modified to having no virulence, make vaccines that don’t make people ill
  • used as vectors in gene therapy
89
Q

Negative of GM pathogens

A

-uses of viruses in gene therapy, allele may be inserted into genome in a way that increases risk of cancer or interferes with gene regulation

90
Q

Positive of GM animals to produce pharmaceuticals

A

-gene inserted into goats or sheep and they produce human protein in their milk

91
Q

Negative of GM animals to produce pharmaceuticals

A

welfare of GM goats and sheep

however, valuable and well looked after

92
Q

Issues relating to patenting and technology transfer

A

making genetically modified seed available to poor farmers

93
Q

difference between somatic and germ line gene therapy?

A

somatic can target specific tissues in need of treatment

germline cannot

Biology A2 Rafa (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions