Presentation on theme: "Biotechnology Unit 6. I. What is biotechnology? Biotechnology is a the use of living systems and organisms to develop or make useful products. Today we."— Presentation transcript:
I. What is biotechnology? Biotechnology is a the use of living systems and organisms to develop or make useful products. Today we try to use biotechnology to find new medical cures, to increase agricultural yields, to find new fuel sources or solutions to various environmental problems. We use DNA tools to modify the DNA of organisms to produce useful products. These organisms are called genetically modified organisms (GMO’s).
We can genetically modify organisms by: – altering the DNA of existing genes to modify proteins coded from the genes – Adding a foreign gene to an organism – these are called transgenic organisms – Deleting or turning off existing genes. http://www.radiolab.org/story/91607-intelligent-design/http://www.radiolab.org/story/91607-intelligent-design/ -- biotechnology http://www.radiolab.org/story/91602-genes-on-the-move/http://www.radiolab.org/story/91602-genes-on-the-move/ -- MIT students at 9:15
II. Important Research Methods Used by Biotechnology A.DNA Sequencing Used to determine the nucleotide sequence of a given gene or an entire organism. During sequencing, DNA molecules are cut into fragments. Than these fragments are copied many times. These copied are separated to single-strand DNA molecules and the complementary nucleotides are added one at a time while electronic monitors detect which nucleotide was added at each time. This method could be used to study the DNA of entire organisms, paternity cases, genetic testing, evolutionary research, etc.
B. Restriction Enzymes These are special enzymes originally found in bacteria that cut DNA at certain sequences (recognition sites). Some enzymes cut between the base pairs of the DNA and create sticky ends, that can be attached to new parts of a DNA molecule. Other enzymes cut across the double helix and create blunt ends. This method can be used to cut “gaps” in a large DNA molecule and than insert a new gene into the DNA.
C. Ligation The process of reassembling DNA fragments by using DNA ligase enzyme is called ligation. When DNA from different sources (different organisms) is assembled by this process, we call it recombinant DNA. http://www.dnalc.org/view/15487-DNA- ligation-3D-animation-with-no-audio.html
D. Gel Electrophoresis Gel electrophoresis is a method that separates large molecules (like nucleic acids and proteins) on the basis of their size, electric charge and other properties. The DNA for this is usually cut into smaller pieces by restriction enzymes, than injected into a gel. Electric current is run through the gel and the molecules are dragged along in the gel by the current. Smaller molecules run further than larger ones, than they are compared to a standard. This method is used to identify and separate segments of DNA molecules for further study, copying or sequencing, used to purify DNA, to detect mutations, to identify individuals etc.
E. Polymerase Chain Reaction (PCR) This method is used to amplify (copy) segments of DNA molecules (genes) that scientists are interested in studying. Within hours PCR can generate millions of copies of DNA from very small amounts. The copied segments can be used for a wide range of purposes. For example to insert a gene into an organism, to sequence the DNA, to be used for crime scene investigations, etc. http://highered.mheducation.com/sites/0072437316/student_view0/chapter16/animations.html http://www.cnpg.com/video/flatfiles/539/ -- PCR song http://www.cnpg.com/video/flatfiles/539/
III. How Can Biotechnology Benefit Us? This list is just a short one on how biotechnology can benefit us today: We can insert genes into bacteria to make useful enzymes and hormones for us. Such as insulin for diabetics, enzymes to make cheese and other food products, antibiotics and other drugs. Golden rice is genetically modified to provide vitamin A to people who would have low levels of this vitamin because of rice centered diet. Soy, cotton and other plants are genetically modified to be herbicide resistant.
Plants can be genetically modified to be undigestable or unedible for insects Plants can be genetically modified to grow faster and yield more food for us Bacteria or other organisms can be modified to produce vaccines for us against harmful pathogens Bacteria can be genetically modified to digest spilled oil or other toxins to clean up the environment. Immunglobulins can be modified to specifically act against certain cancer cells etc.
IV. What Are The Threats? Biotechnology has to be applied carefully and every new product needs to be tested out thoroughly before it is introduced into use. There are some dangers: – Superbugs, pathogens may be produced – Disruptions in the food chains – We may create undigestable or dangerous chemicals in crops or livestock – Ethical issues, like who should know your genetic makeup, your mutations, should we alter other organisms