Transcript Notes april 16 and 17 - Salmon River High School

Notes pg 26-thru end of book
Transforming Bacteria
Question: What happens during cell
transformation?
Answer: During transformation, a cell takes
in DNA from outside the cell. The
External
_______________
DNA becomes a
component of the cell's DNA.
______________
joined
Foreign DNA is first_____________
to a small,
circular DNA molecule known as a plasmid.
Plasmids are found ____________in
some
naturally
bacteria and have been very useful for DNA
transfer.
The plasmid has a ______________
genetic
marker—a gene that makes it possible to
distinguish bacteria that carry the plasmid
(and the foreign DNA) from those that don't.
Example: Diabetic humans don’t produce enough insulin
to control the amount of sugar in their blood. We used to
harvest insulin from horses. Now, however, thanks to
gene splicing we’re able to splice our genes for insulin
production into bacteria. We grow the bacteria in large
vats and produce large amounts of human insulin for a
fraction of the cost.
Transforming Plant Cells
Question: How can
you tell if a
transformation
experiment has been
successful?
Answer: If transformation is successful,
Recombinant
the _________________DNA
is integrated
into one of the chromosomes of the cell.
A) In nature, a ________________
exists that
bacterium
produces tumors in plant cells.
remove
Researchers can _____________the
tumorproducing gene found in this bacterium and insert
a piece of foreign DNA into the plasmid.
The bacteria with the _______________
recombinant plasmid
can then be used to infect plant cells.
B) When their cell walls are removed,
plant cells in culture will
sometimes
________________
take up DNA on their
own.
C) DNA can also be _____________
injected
directly into some cells.
Cells transformed by either procedure
Cultured
can then be _________________
to
produce adult plants.
Many egg cells are ___________
large
enough that
DNA can be directly injected into the nucleus.
Enzymes may help to___________
insert
the
foreign DNA into the _______________
chromosmomes of
the injected cell.
DNA molecules used for transformation of
animal and _________
cells contain marker
plant
genes.
DNA molecules can be constructed
with two ends that will
sometimes
________________
recombine
with specific sequences in the host
chromosome.
The host gene normally found
between those __________
two
sequences may be lost or
replaced with a new gene.
Transforming Bacteria
Question: What happens during cell
transformation?
Answer: During transformation, a cell takes
in DNA from outside the cell. The external
DNA becomes a component of the cell's
DNA.
Foreign DNA is first joined to a small,
circular DNA molecule known as a plasmid.
Plasmids are found naturally in some
bacteria and have been very useful for DNA
transfer.
The plasmid has a genetic marker—a
gene that makes it possible to distinguish
bacteria that carry the plasmid (and the
foreign DNA) from those that don't.
Transgenic Organisms
An organism
described as
transgenic,
contains genes
from other
species.
Question: How are transgenic organisms
useful to human beings?
Answer: Genetic engineering has spurred
the growth of biotechnology.
Transgenic Animals
Transgenic animals have been used to study
genes and to improve the food supply.
Mice have been produced with human
genes that make their immune systems
act similarly to those of humans. This
allows scientists to study the effects of
diseases on the human immune
system.
Researchers are trying to produce
transgenic chickens that will be
resistant to the bacterial infections
that can cause food poisoning.
Transgenic Microorganisms
Transgenic bacteria
produce important
substances useful for
health and industry.
Transgenic bacteria have
been used to produce:
insulin
growth hormone
clotting factor
Transgenic Plants
Transgenic plants are now an
important part of our food
supply.
Many of these plants contain a
gene that produces a natural
insecticide, so plants don’t have to
be sprayed with pesticides.
Cloning
A clone is a member of a population of
genetically identical cells produced from a
single cell.
In 1997, Ian Wilmut cloned a sheep
called Dolly.
Researchers hope cloning will enable them
to make copies of transgenic animals and
help save endangered species.
Warning! Studies suggest that cloned
animals may suffer from a number of
genetic defects and health problems.
In class
Do question 32-43
pg 46 in workbook
turn in answers as a
HW grade on the
sheet provided.