Manipulating genomes

• Genome = all the genetic material an organism contains
• proteome = all the proteins a cell can produce
• Introns are non-coding DNA consisting of many STRs
• What can be determined by the analysis of STRs?

  Determines how closely related organisms are.
• What are the stages of genetic fingerprinting ?

  Collection

  Extraction

  Seperation

  Hybridisation

  Development

  Analysis
• What is needed for PCR ?

  Taq polymerase

  Thermocyler

  Primers

  DNA nucleotides
• What happens in each stage of PCR ?

  1. Temperature is increased to break hydrogen bonds
  2. Temperature lowered so primers can anneal
  3. Temperature increased so taq polymerase can catalyse the condensation reaction between bases forming the new strands.
• What are 3 advantages to PCR?

  Automated

  Rapid

  Doesn't require living cells
• telomeres = found at end of gene
• satellite DNA = short sequences of repeating DNA codes within intons, centromeres and telomeres
• Uses of comparing genomes ?

  1. examine evolutionary relationships
  2. identify essential life genes
  3. identify genetic polymorphisms
  4. DNA profiling
• In genetic fingerprinting how is DNA separated ?

  Via electrophoresis.
• Describe the principles of electrophoresis ?

  DNA samples are loaded into small wells in agar gel, placed in a buffer liquid with an electrical voltage. DNA moves through the gel towards the positive electrode with the smaller fragments travelling faster through the gel.
• Restriction enzymes cut DNA at recognition sites.
• What is the first step in sequencing a plant genome?

  PCR is performed on all the DNA
• What components are mixed in the thermocycler for sequencing?

  DNA, DNA polymerase, terminator bases, primer, nucleotides
• What role does DNA polymerase play in sequencing?

  It adds complementary bases to create new strands
• How do terminator bases function in the sequencing process?

  They terminate DNA synthesis at random points
• What are terminator bases ?

  Dideoxynucleotides
• What is the difference between the original Sanger method and modified version ?

  In the original 4 test different tubes each containing 1 type of terminator base, each tube requires its own electrophoresis. In the modified method all the terminator bases can be combined in a singular test tube, each base is attached to a fluorescent dye so they can identify which base is which.
• Computational biology is the use of data to build theoretical models of biology systems which can be used to predict what will happen in different circumstances.
• Genomics is the use of DNA sequencing and computational biology to analyse the structure and fucntion of genomes.
• What is the advantage to genomics ?

  Cheaper and faster.
• Name two uses of genomics in the medical field ?

  Identify antibiotic resistant strains

  Track and monitor outbreaks of potentially serious disease
• What is DNA barcoding ?

  Comparison of particular sequences of the genome common to all species to aid the classification of organisms.
• Name 3 uses of genomics ?

  1. Classification of organisms by DNA barcoding
  2. Medical advances
  3. More accurate identification of evolutionary relationships
• How can genomics identify evolutionary relationships ?

  Calculate basic mutation rate of DNA, allowing scientists to calculate how long ago two species diverged from a common ancestor.
• Synthetic biology is the design and construction of novel artificial biological pathways, organisms or devices and the redesign of existing natural biological systems.
• What techniques are used in synthetic biology ?

  Genetic engineering

  Use of biological systems in industrial context

  Synthesis of new genes

  Synthesis of entire new organisms.
• Why may new genes need to be synthesised by synthetic biology ?

  To replace faulty genes.
• Give an example of use of biological systems in industrial context ?

  Use of enzymes in the production of drugs.
• What happens to Pre-mRNA after it is transcribed ?

  Spliced by spliceosome enzyme complexes to remove introns to form mRNA.
• Why is mRNA modified ?

  To create variation of phenotypes from the same genotypes.
• Where does RNA splicing occur ?

  In the cytoplasm near the ribosomes.
• Order the respiratory substrates starting with what releases the most energy?

  Carbohydrates

  Protein

  Lipid
• Genetically modified organisms are organisms that have had their genomes altered by gentic engineering techniques.
• Why do scientists develop genetically modified organisms?

  To utilise the organisms desirable phenotypes.
• Transgenic organism = an organism that contains recombinant DNA
• Recombinant DNA = a DNA molecule that contains DNA from more than one organism.
• Why can transgenic organisms successfully express all their genes ?

  Because the genetic code is universal