Transcript GM skills - KingsfieldBiology

What is the link?
Objectives
E – Describe the process of
genetic engineering
C – Explain the advantages
and disadvantages and
interpret data
A – Evaluate the technology
The tools of gene technology
• Restriction
endonucleases –
allow DNA to be cut
• Reverse
transcriptase –
copies DNA
• DNA ligase – rejoins
DNA
DNA Ligase
Recombinant
DNA
Restriction
endonuclease
Sticky ends
Inserting genes
• Plasmids can be cut open with restriction
endonucleases
• If a gene is cut out with the same enzyme they
will have complementary sticky ends
• DNA ligase seals up the gap in between by
forming a phosphodiester bond
How do you know if a cell has
been transformed?
• Radioactive probe
– Complementary to DNA
– DNA hybridises with the probe
– Those cells are selected and grown up to
obtain a pure culture of those cells
• Antibiotic resistance
– Cells which have taken up the plasmid will
grow on the medium
Applications
Agricultural:
Industrial:
Medical:
•Flavr savr
tomato ripens
slower
•Enzymes
produced cheaply
in large amounts
(chymosin)
•Hormones
(growth
hormone, insulin)
•Golden Rice
produces more
vitamin A
Conversion of mRNA to cDNA, using
reverse transcriptase.
• Activity:
– Now that you know the
correct sequence
complete the cut and
stick worksheet to put
the synthesis of cDNA
into the correct order
– Add any extra details
about the process which
is occurring
Conversion of mRNA to cDNA, using
reverse transcriptase.
• Activity:
– Now that you know the
correct sequence
complete the cut and
stick worksheet to put
the synthesis of cDNA
into the correct order
– Add any extra details
about the process which
is occurring
cDNA
• cDNA is DNA formed from an mRNA
template using reverse transcriptase
– Requirements are:
•
•
•
•
primers
dNTPs
Reverse transcriptase
DNA polymerase
• Reverse transcriptase works first followed by
DNA polymerase
• (RNAase can be used to digest unwanted
RNA)
Reverse Transcriptase
mRNA  cDNA
Four basic reagents are needed to
produce cDNA: mRNA as template,
dNTPs, reverse transcriptase and
primers.
Owner of a biotechnology company
Environmental activist
Government official responsible for issuing public
announcements on the technology
Archbishop of Canterbury responsible for the moral
decisions of 60% of the UK.
Less pesticides
need to be used
for resistant
crops.
No idea what will
happen when new
genomes are
released into the
environment
No one knows
the health risks
of GM foods
No one has the
right to mess
with teleos
Hormones can be
produced that
will not be
rejected when
put in to humans
Flavr savr
tomatoes do not
require
chemicals to
stop ripening.
Better for
health?
Multinationals
think they are
God creating and
patenting life
Not that
different from
selective
breeding but
less inbreeding
necessary
Genetic
“mistakes” are
made on purpose
Is this paving
the way to
eugenics,
selectively
breeding humans
Objectives
E – Describe the process of
genetic engineering
D – Explain the advantages
and disadvantages
C – Evaluate the technology