Study Guide final exam Chapter 19 Genetic Technologies What is the underlying reason why biotechnology is possible use or alteration of specific cells or biologic molecules for specific application Transgenic organisms are possible because the genetic code is universal What does PCR stand for polymerase chain reaction What does PCR do amplifies DNA by increasing the amount of DNA sequence in a tube and replicates sequences millions of times What are the four components needed for a PCR reaction and what do they do Polymerase finishes replicating DNA Primers hybridize due to base complementarity Free nucleotides Target sequence What is recombinant DNA Molecule that combines DNA from TWO SOURCES also known as gene cloning This creates a new combination of genetic material What is a restriction enzyme and how does it work restriction enzymes are cut DNA from the donor and recipient with the same restriction enzyme at specific sequences This cut DNA fragment is combined with a vector then the vector is cut with the same restriction enzyme Donor DNA and vector DNA combine The complimentary ends of the DNAs bind and ligase ezymes reattaches the sugar phosphate backbone of DNA What are sticky ends DNAs that are cut from two sources with the same restriction enzyme have sticky ends These two pieces of DNA hydrogen bond and ligase seals the sugar phosphate backbone What kinds of vectors are used with recombinant DNA vectors are classified as organisms that replicated the vector and the size of DNA hat can be inserted Types Plasmid bacteriophage bacterial artificial chromosome BAC and yeast artificial chromosome YAC How does a genomic library differ from a cDNA library Genomic libaray collections of recombinant DNA that contain pieces of the genome cDNA library genomic library of proteins encoding genes produced by extracting mRNA and using reverse transcriptase to make DNA What is reverse transcriptase What is cDNA How are antibiotic resistance genes used in recombinant DNA technology 3 types of cells can result from an attempt to indroduce DNA molecule into bacterial cell 1 Cells lack plasmid 2 Cells contain plasmid that do not contain foreign genes 3 Cells that contain plasmids with forgein genes Vectors are engineered to carry antibiotic resistance genes Host bacteria without a plasmid DIE in the presence of the antibiotic Bacteria harboring the vector SURVIVE All growing cells must carry the vector What are transgenic organisms when recombinant DNA is applied to multicellular organisms individuals must be bred to yield homozygous individuals Plants may be produced by asexual reproduction cutting and different vectors and gene transfer techniques can be used Why is it easier to make transgenic plants than transgenic animals plants are easier than animals because there are several techniques involved with animals What does the bt gene do insecticide gene is from bacterium BACILLUS THURINGIENSIS and specifies a protein that destroys the stomach lining of certain insect larva Know the benefits and risks of GM genetically modified crops BENEFITS Greater control than traditional agriculture because single traits are manipulated enhanced nutritional qualities added vitamins minerals nutrients that protect against cancer resistance to pests disease and environmental extremes delayed fruit ripening to extend shelf life delayed potato development to reduce need for chemicals to suppress sprouting elimination of allergens bioremediation of toxins and explosives changes in proteins fats carbs that serve as raw materials for paper lubricants detergents food control of plant height flowering time seed size number produces more of the edible version of the plant less phosphorus to animal feces making groundwater contamination less likely to cause algal blooms RISKS escape of transgene beyond field economic and political repercussions of displaced traditional products harm to farmers and US companies as other nations boycott GM products unexpected results from combinations of genes from different species inability to predict long term consequences of introducing GM organisms into the environment reduction of biodiversity What is bioremediation transgenic organisms that can provide process as well as products They have the ability to detoxify pollutants What are DNA microarrays and what kinds of questions can they address deletions and amplifications of DNA sequences between cells or species Silencing DNA can be useful for blocking transcription of oncogenes Has 3 techniques to control gene expression 1 RNA interference 2 Antisense sequences 3 Knockouts from gene targeting How do the following techniques prevent the expression of genes RNA Interference single stranded RNAs can fold into short double stranded regions hairpins when the sequence is complementary This block in translation is RNA interference Antisense Sequences antisense induced exon skipping silences mutations that cause exons to be cut out of maturing mRNA The original mutation is bypassed enabling production of full length protein Knockout Genes uses GENE TARGETING which is technique that uses homologous recombination to replace a normal DNA sequence with one that cannot be transcribed or translated This silences gene expression by creating a knockout gene Chapter 20 Genetic Testing and Treatment What are some of the reasons to seek genetic counseling family Hx of abnormal chromosomes elevated risk of single gene disorder family Hx of multifactorial disorder family Hx of cancer What types of genetic tests are available population carrier screen heterozygotes people with one copy of a mutant gene prenatal test to test mutant alleles prenatal screen tests embryo or fetus for the risk of a condition newborn screen diagnostic tests predisposition test predictive tests What are some concerns about direct to consumer genetic tests regulation of genetic tests remain somewhat unclear CLIA regulations and certification How does enzyme replacement therapy work recombinant human enzyme infused to compensate for deficient or absent enzyme What is Type 1 Gaucher disease lysosome storage disease lysosomes take in substrate toxins and without the enzyme to break down these toxins they will build and eventually burst and dump the substrate toxins into the cell and kill the cell What are some of the approaches used to combat this disease enzyme replacement therapy substrate reduction therapy pharmacological chaperon therapy What is gene therapy