Download Genetic Engineering

- making changes to the
DNA code of a living
organism
Standard 5c
Students know how genetic engineering
(biotechnology) is used to produce novel biomedical
and agricultural products.
Standard 5d
Students know how basic DNA technology (restriction
digestion by endonuleases, gel electrophoresis,
ligation, and transformation) is used to construct
recombinant DNA molecules.
Standard 5e
Students know how exogenous DNA can be inserted
into bacterial cells to alter their genetic makeup and
support expression of new protein products.
Old Style Genetic Engineering
Selective breeding – using hybridization and
inbreeding to pass desirable traits onto
future generations (dogs)
Modern Genetic Engineering
Cloning – make an identical copy of DNA (a
segment or the whole nucleus)
PCR (Polymerase Chain Reaction) - to make
many copies of a specific segment of DNA
- allows individual GENES to be studied
Step 1 – DNA extraction
- use a restriction enzyme to cut DNA at a
specific base sequence producing exogenous DNA
fragments with “sticky ends”
Step 2 – Insertion
- putting the exogenous DNA into a vector by
matching “sticky ends”
Vectors – bacterial plasmids and viruses
Plasmids – circular DNA
molecule into which the
exogenous gene is inserted
-this DNA in the host cell makes
the host cell produce something it
normally would not
Step 3 - Transformation
- host cells take up the
recombinant DNA
Step 4
Grow many of the
recombinant cells.
- the product is extracted
from the cells or the
medium the cells are
grown in
- the product is then
purified
Some of these commercially cultured products
come from genes for :
- human insulin
- human growth
hormone
- blood clotting factors
In modern agriculture, this technology is
used to insert genes that:
- increase the productivity of
food crops and animals
- promote resistance to
viruses, pests, and herbicides
- promote robustness under
harsh environmental
conditions
5 Essential Questions Biotechnology
1. What is genetic engineering or biotechnology?
2. Give examples of how biotechnology is used in
medicine and in agriculture.
3. What is recombinant DNA?
4. Explain how recombinant DNA is made. Tell
how restriction enzymes are used to put an
exogenous gene into a plasmid.
5. What is electrophoresis? When and how is it
used?