Lab 7 Flashcards
biotechnology
the use of organisms or their components to make or modify products useful to humans
traditional biotechnology
- selective plant and animal breeding
- yeast in fermentation to produce cheese, bread, beer and wine
modern biotechnology
-manipulation of DNA in vitro
Each DNA strand is composed of a series of….
nucleotides
Nucleotides are composed of…
- nitrogenous base,
- sugar (deoxyribose)
- phosphate group (negatively charged)
Nucleotides are joined by covalent…..
phosphodiester bonds
Between the two strands of DNA, ____________ are formed between ____________________.
- hydrogen bonds
- complementary nitrogenous bases (AT/GC)
Biological samples collected for DNA analysis must contain ___________ cells.
-nucleated (bodily fluids, hair follicle w/ root attached, skin, organs, and bones)
What are the steps in processing and analyzing DNA
- DNA extraction
- Polymerase Chain Reaction
- Restriction fragment analysis
- interpreting the results
List the 3 solutions used in DNA extraction and describe them.
- sports drink: is isotonic to environment inside the cheek cells so cells will not burst + release DNA prior to collection
- detergent (cell lysis sol’n): lyses the plasma membrane and nuclear membrane of each cell
- ethanol: DNA is insoluble in alcohol so it precipitates out of the sol’n into the ethanol layer
What are the 4 ingredients required for PCR
- DNA extract
- 4 dNTPs (dATP, dCTP, dGTP, dTTP)
- primers
- DNA polymerase (Taq polymerase)
What are the 3 steps in each PCR cycle?
- DNA denaturation: heat to separate strands
- Anneal primers: cool so primers can bond to strands
- Extend primers: heat to allow DNA polymerase to add dNTPs to the end of the primers (DNA synthesis)
What are the steps in Restriction Fragment Analysis?
- restriction digest
- gel electrophoresis
Restriction Digest
restriction digest of the PCR product
- a restriction enzyme is added to the PCR product
- the sol’n is placed in an incubator
- enzyme cuts theDNA in the PCR product into specific fragment sizes and numbers
The restriction enzyme EcoRI recognizes and cuts DNA within the nitrogenous base sequence….
GAATTC.
restriction fragments
the resulting lengths of DNA from restriction digest
gel electrophoresis
a process that allows us to separate the restriction fragments produced by each digested PCR product into an ordered group, based upon molecular size differences
DNA is _______ charged
negatively
The principle of gel electrophoresis is based on …
- the negative charge of DNA
- the differences in size of the DNA fragments
What is the gel used in gel electrophoresis?
-agarose
What stain is used in gel electrophoresis and why?
-Fast Blast, which can be visualized with white light
recombinant DNA
when DNA from two different sources are combined into one molecule
GMO
- genetically modified organism or transgenic organism
- an organism that has acquired genes through any artificial process, including recombinant DNA technology
restriction fragment analysis
-process that enables an indirect comparison of nucleotide sequences in diff. amplified DNA samples
Th gel is submerged in a chamber containing salt water because….
it conducts electricity
List and describe 3 examples of modern biotechnology and how they benefit humans.
- insulin is manufactured by inserting the gene for insulin into a plasmid (recombinant DNA) which people take to regulate they blood sugar
- cells are modified in calfs with genes for producing lysostaphin, a protein that kills staphylococcus aureus bacteria, which leads to mastitis disease in cows.
- genetic modification of livestock to enable expression of selected genes in their mammary cells like important proteins for dissolving blood clots and treating hemophilia and emphysema are purified from the milk of transgenic animals.
- tissue culture techniques are used to clone many different kinds of natural and transgenic plants with desirable genetic traits for use agricultural production, forestry and scientific research
