topic 6.1.3: manipulating genomes Flashcards
what is a genome
the genetic material of an organism
what are the ingredients of dna sequencing
dna polymerase, primer, excess of nucleotides, terminator bases, dna to be sequenced mixed in a thermocycler
what are the principles of dna sequencing
dna p adds comp bases to dna, creating new strand
terminator bases added at diff points, creating every possible length
each base labelled with fluorescent dye
gel electrophoresis separates according to size
what is high throughput sequencing
many fragments processed and sequenced simultaneously
what are the benefits of genome wide comparisons
identify sources of infections, identify resistant bac, track spread of pathogens
what is synthetic biology
creation of artificial organisms or devices, or redesign of natural systems eg genetic engineering, synthesis of genes
what is bioinformatics
use of software to analyse and store data
what is computational biology
use of computers to study biology eg modelling
what are introns made up of
variable number tandem repeats
what are vntrs
sequences where nucleotides are repeated a variable number of times, meaning they are different lengths in individuals
what are the 6 stages of dna profiling
extraction, digestion, separation, hybridisation, development, analysis
what happens in the extraction stage of dna profiling
small fragment multiplied by pcr
what happens in the digestion stage of dna profiling
restriction endonucleases added to cut dna into smaller pieces
what happens in the separation stage of dna profiling
gel electrophoresis
what happens in the hybridisation stage of dna profiling
fluorescent or radioactive probes added in excess and bind to dna
what are probes
short complementary fragments
what happens in the development stage of dna profiling
southern blotting:
strands transferred to nylon membrane and exposed to x rays to visualise position of probes
what happens in the analysis stage of dna profiling
bands compared to identify relationships, presence of disease, or match unknown samples
what equipment is needed for a polymerase chain reaction
thermocycler, dna fragment, primers, taq polymerase, nucleotides
why is taq polymerase used
thermophilic bacteria thrive in hot conditions, work faster
what are the principles of pcr
95: h bonds broken, dna split
55: annealing
72: synthesis
describe the process of electrophoresis
samples loaded into agar plates, ph buffer added and voltage applied to cathode end
dna move to pos end
alkali added to denature strands
what are the 4 stages of genetic engineering
identification, removal, insertion, transformation
what happens in the identification stage of genetic engineering
desired gene selected in organism and plasmid
what happens in the removal stage of genetic engineering
remove gene and section of plasmid with restriction endonucleases
what happens in the insertion stage of genetic engineering
dna put into plasmid using dna ligase to anneal sticky ends (phosphodiester bonds)
what happens in the transformation stage of genetic engineering
recombinant plasmid into bacteria host cell by electroporation, marker genes mark which genes took up plasmid
what is electroporation
electrical current applied to increase cell’s permeability
how are soya plants genetically engineered
addition of gene to produce bt protein which is toxic to pests
what are the risks and benefits of genetically engineering plants
reduces needs for pesticides, maximises yield, bur may spread to env
what are some reasons that plants may be genetically engineered
maximise shelf life, nutritional value, produce medicine
what does patented mean
certain groups are excluded from being able to use an invention ie poorer farmers
how are animals genetically engineered
modified viruses are injected to carry new genes
what is pharming
inserting a human gene into bacteria to produce a human protein
what are the risks and benefits of pharming
research and vectors
increased antibiotic resistance, disruption to expression or regulation of genes
what is gene therapy
treatment of genetic disorders by altering dna
what are the principles of gene therapy
cells isolated from patient, viral vector inserted, cells injected or inhaled
what is somatic cell gene therapy
some cells are replaced- temporary
what is germ line cell gene therapy
alteration of dna in gametes so offspring doesn’t inherit faulty gene- permanent