Biotechnology

Página 1

Definition: any use or alteration of organisms, cells or biological molecules to achieve specific goals

genetic material is modern and works to improve upon nature

organisms that have been changed have changed their genes by deleting them or adding them

Recombinant DNA Technology: the use of DNA that has been altered to contain genres or portions of genes from different organisms

transgenic= GMO's, these plants or animals have been altered to express a new type of DNA

Genetic Recombination in Nature: crossing over in meiosis

bacteria regular undergo recombination that allow genes to transfer between species

transformation= bacteria pick up pieces of DNA from the environment

these pieces may be from different bacteria or tiny DNA molecules called plasmids

Plasmids

plasmids are released when a bacterium dies

these can be taken up by different organisms which moves genes between prokaryotic and eukaryotic cells

Role of Viruses in DNA Transfer

viruses have DNA and RNA that they can transfer into the organisms they infect by inserting their own DNA into a cell chromosome

this makes the chromosome and DNA replicate the viruses which then spreads throughout the organism

The Polymerase Chain Reaction

virtually produces unlimited amounts of DNA

DNA polymerase binds to a primer and brings in the complimentary nucleotides

flanking sequences= already known nucleotide sequence and are on either side of the piece of DNA of interest

Steps of PCR

heating and cooling are repeated many times to generate enough copies of the DNA segment

1-2-4-8-16-32 (always doubled after the first round)

DNA strand is unwound and separated by heating

primers bind to complementary bases on the now single DNA strand

new DNA strand by DNA polymerase that starts from primers

result: two new helixes composed of the original stand plus new complementary strand

But heating DNA can denature it...

Tay polymerase, a heat resistant DNA polymerase

was isolated from bacteria in hot springs

before, scientists would have to add a new DNA polymerase every time one was ruined

In Forensics

can produced unlimited amounts of DNA even from the tiniest sample

In Agriculture

grow as much food, cheap, and minimal loss from pests

transgenic plants

plants are given a gene called Bt that encode for a protein that damages the digestive tract of insects but not animals

How are transgenic plants made?

the desired gene is cloned

gene is inserted into a small piece of DNA in bacteria called plasmids using restriction enzymes

restriction enzymes= cuts DNA at a specific nucleotide, leaving sticky ends that bind to pieces of DNA with complementary bases

when Bt genes and plasmids are combined, it creates a permanent bondage by DNA ligase