click below
click below
Normal Size Small Size show me how
Ch 26
Exam 2: Recombinant DNA and Biotechnology
| Question | Answer |
|---|---|
| the production of identical copies through some asexual means | cloning |
| examples of clones | bacteria in a colony all come from the same original cell and therefore are clones; human identical twins |
| sections of DNA that express a characteristic | genes |
| the production of many identical copies of the same gene | gene cloning |
| DNA put together from 2 or more different sources | recombinant |
| (restriction endonucleases) produced by cells to _____ any _____ in order to protect the organism | chew up any foreign DNA |
| (restriction endonucleases) many recognize and _____ specific sequences | cut at |
| (restriction endonucleases) most do not cut the double strand _____, they... | evenly; leave ends that overhang by 4 to 8 bases (sticky ends) |
| 2 DNA fragments that have been cut with the same enzyme can be... | stuck together |
| an enzyme called _____ can repair the break in the backbone joining them permanently | DNA ligase |
| many organisms in addition to their main chromosomes have small, circular bits of DNA called _____ | plasmids |
| plasmids usually only carry only a few _____ | genes |
| plasmids replicate _____ of the main chromosomes | independently |
| cells can have from _____ to ______ copies of plasmids | one to several thousand |
| plasmids can be used to produce _____ in bacteria or yeast (cloning) | foreign DNA |
| recombinant DNA technology: cut target DNA with ... | restriction endonuclease |
| recombinant DNA technology: cut plasmid DNA with... | the same endonuclease |
| bond complementary sticky ends | anneal |
| attach permanently | ligate |
| transfer the recombinant plasmid into... | an E. coli or yeast |
| E. coli | prokaryote |
| yeast | eukaryote |
| as the E. coli or yeast reproduce, it produces... | more genes or more of a product like insulin |
| PCR | Polymerase Chain Reaction |
| PCR: creates copies of DNA _____ in a test tube | very quickly |
| PCR: makes lots of copies of... which can be less than one part per million of the total DNA sample | targeted sequence of DNA |
| PCR: uses _____ (the enzyme that carries out DNA replication) to cause a chain reaction that continues until the process is stopped | DNA polymerase |
| (analyzing DNA segments) 1st PCR is used to _____ the amount of DNA that we are interested in | increase |
| (analyzing DNA segments) then the DNA is treated with _____ | restricted endonucleases (this creates a unique collection of different-sized fragments) |
| (analyzing DNA segments) the DNA is then placed into a process called _____ | gel electrophorosis |
| (gel electrophorosis) a gel of _____ with wells in the top is poured | agarose |
| (gel electrophorosis) DNA that has been cut with _____ is placed into the wells | endonucleases |
| (gel electrophorosis) an electric current is run across the gel with the _____ charge at the bottom | positive |
| (gel electrophorosis)the negatively charged DNA fragments move toward the _____ charge | positive |
| (gel electrophorosis) smaller fragments move _____; larger fragments move _____ | (small) faster; (large) more slowly |
| (gel electrophorosis) the sample forms a _____ of DNA fragments of increasing size | "ladder" |
| DNA is collected at... | the crime scene and from crime suspects |
| DNA is exposed to _____ and put into _____ | restriction enzymes; gel electrophoresis |
| different people have... | different sequences of DNA |
| different sequences means different... | "ladders" will show up in the electrophoresis |
| if a suspect's DNA "ladder" matches the crime scene DNA ladder, then... | the 2 DNA samples come from the same person |