biotechnology Flashcards
what is recombinant DNA technology (genetic enineering)
introducing DNA into a cell from a different type of organism or DNA that has been modified in some way
the DNA produced in cell recombinant DNA
the organism is genetically modified organism (GMO)
what is a transgenic organism
is one which has genetic material from another organism artificially inserted
what are two examples of transgenic organisms
golden rice
glofish
what is golden rice
Golden rice is a genetically modified, biofortified crop. biofortification increases the nutritional value of crops
golden rice is genetically modified to produce beta-carotene, which is not normally present in rice, beta-carotene is converted into vitamin A when metabolized by the human body
what is glofish
glofish are a type of transgenic zebrafish (danio-rerio) that have been modified through the insertion of a green fluorescent protein (gfp) gene
descrive the process of cutting DNA
DNA is cut using a chemical called an endonuclease (e.g. restriction enzyme)
restriction enzymes are found in bacteriophages (viruses that infect bacterial cells)
restriction enzymes cut DNA at specific points of certain sequences (called recognition site)
recognition sites are palindromic (read the same forwards and backwards e.g radar)
what are the two different cuts that can be made in DNA
sticky ends
blunt ends
what are sticky ends
some restriction enzymes, such as HindIII, make staggered cuts in DNA producing single-standarded, cohesive (sticky ends)
what are blunt ends
other restriction enzymes, such as pvuII cut both strands of DNA straight across, producing blunt ends
what is the process of naming enzymes
the first letter of the name comes from the genus of the bacterium from which it was isolated
the second two letters come from the species
the next letter refers to the strain of the bacterium
the roman numerals represent when the enzyme was isolated, when I is the first enzyme isolated, II is the second enzyme isolated etc
describe an exmaple of naming an enzyme
for example, EcoRI is the first restriction enzyme isolated from the RY13 strain of the bacterium Escherichia Coli, while HindIII is the third enzyme isolated from the R(d) strain of the Haemophilus influenza bacterium
what is DNA ligase
the ‘glue’ that sticks fragments of DNA together
joins the phosphate group at the other end of one strand to the sugar molecule at the end of another strand (after the complementary bases forms hydrogen bonds)
how does recombinant DNA work
- gene is isolated and cut using a restriction enzyme
- isolate a plasmid (a circular piece of DNA in a bacterial cell) and cut it with the same restriction enzyme
- use DNA ligase to splice (bind) the gene (donor DNA) into the vector (plasmid)
- treat the bacterium so that the recombinant DNA is taken up into the cell
- bacteria is left to divide and produce clones
- bacteria will now be able to produce the protein using the donor (e.g insulin)
