CP Biotechnology

13.1 Biologists Manipulate DNA

• Scientists use biotechnology to perform practical tasks

• Today, we mainly manipulate the genomes of organisms.

• We called this act of manipulation DNA technology.

Bacteria – Common VectorBacteria are commonly

worked with in biotechnology because they can acquire new genes in many ways!

1. “Tunnel” forms a bridge between the bacteria where DNA can travel.

2. Transformation – bacteria can “take up” free floating DNA into their own DNA

Recombinant DNA technology - technology

involving the combining of DNA and/or genes from different sources (even genes from different species).

Uses of DNA technology:1. Make more nutritious crops (ex. Corn)

2. Make medicine in large quantities

3. Help us understand specifically how gene sequences work

13.2 Engineering Bacteria

• Bacteria contain plasmids

• Plasmids are small circular pieces of DNA separate from the bacterial chromosome.

• Carry genes (Cool ones!)

Plasmids• Bacteria can transfer plasmids and scientists can

manipulate plasmids to make them useful to us!!

Example: 1. Insert a human insulin gene into a plasmid2. Put the plasmid into bacteria3. When the bacteria reproduce they make many

copies of the medicine!

How Do They Do It???1. Cut

– Use restriction enzymesrestriction enzymes to cut the desired DNA/gene out of a larger chromosome

2. Paste– Put the desired DNA/gene fragment into a plasmid

3. Put the plasmid into a bacterium

4. As the bacterium reproduces it makes many copies of the desired gene!!

Desired Gene

Genetic Engineering creates useful products

1. Bacteria make chemicals that can help clean up hazardous spills

2. Pigs & Cattle make insulin hormone in their milk for people with diabetes

3. Vaccines – make viral proteins to give patients so their bodies make antibodies from it.

13.3 Genetically Modified 13.3 Genetically Modified OrganismsOrganisms

• A genetically modified organism (GMO)genetically modified organism (GMO) is any organism that has acquired any genes artificially.

• If a species is called TRANSGENICTRANSGENIC if it has foreign genetic material from a different species.

Genetically ModifiedGenetically Modified PlantsPlants

Do you eat genetically modified organisms?

YES NO

Just a few…GMO FOODSJust a few…GMO FOODS

• Honey • Cotton

• Tomatoes• Corn

• Vegetable Oil• Peas

• Potatoes

In Groups…

• ½ the class will use their books to compile a list of postive or good reasons/outcomes of using genetically modified organisms (plants and animals)

• ½ the class will use their books to make a list of negative or unwanted reasons to use genetically modified organisms.

Here’s what YOU think…

•

Genetically ModifiedGenetically Modified PlantsPlants• Over 50% of soybean and corn crops were

genetically modified in some way!

• Most common genetic modifications:– Genes for herbicide resistance– Genes to resist insect and fungi pests

Genetically Modified Genetically Modified AnimalsAnimals

• Goals for GMO animals…– Produce mass quantities of hormones (insulin)– Get animals to market quicker (salmon)– Breed animals with better quality products

(sheep wool)– FUN!! $$$$$$$

Few more Few more examples…examples…

The GMO ControversyThe GMO Controversy

Although studies to date have shown that eating genetically modified foods have no negative health affects…people continue to demand

stricter regulations.

Major Concern:Major Concern:

GMO food can pose unknown health risk…request strict labeling laws

**”ORGANIC CRAZE”**

GMO ControversyGMO Controversy

•

13.4 DNA Technologies• Sometimes it is necessary to make many

copies of a piece of DNA from a single sample.

• PCR or Polymerase Chain ReactionPCR or Polymerase Chain Reaction technique can mass produce specific sequences of DNA

Thermocycler

PCR TechniquePCR Technique“make a lot of DNA” from a small sample

Gel Electrophoresis!!!Gel Electrophoresis!!!• Used when you want to compare DNA from

different sources.

• Produces “banding patterns” which can be compared and analyzed.

How it works!

DNA “fragments” move through gel using electric current.

Smaller DNA fragments move further

DNA is cut into “fragments” by restriction enzymes

DNA FingerprintDNA Fingerprint

• Just like every person has their own unique fingerprint…everyone has a unique banding pattern produced by their restriction fragments in gel electrophoresis.

• 97% of our DNA is “junk” or non-coding and is extremely different from any other persons “junk” DNA.

• Forensics!!

Who committed the crime?Who committed the crime?

Bloodstain evidence from crime scene!

Suspect # 1 2 3 4 5 6 7

13.5 Stem Cells and Homeotic Genes13.5 Stem Cells and Homeotic Genes

• Stem cells – cells (early in development) that remain undifferentiated and have the potential to be any type of cell.

• Homeotic Genes – genes that control development of specific locations in organisms.