Natural selection + genetic modification

• Alfred Russell Wallace is a scientist that came up with the idea of natural selection
• Antibiotic-resistant bacteria is bacteria that mutate to become resistant to an antibiotic, surviving and reproducing to pass on their antibiotic resistance
• Archaea is one of the three domains, it consists of primitive bacteria existing in extreme environments
• Arid is a 4.4 million year old female hominid fossil that encompasses both ape and human characteristics
• Biological control is the intruduction of a new organism into an ecosystem to control a pest or pathogen
• Charles Darwin is a scientist who developed the theory of evolution through natural selection
• The three domains are Eukarya, Bacteria and Archea
• Evolution is the gradual change in the inherited traits within an organisms population overtime, it occurs due to natural selection
• Fertilisers are natural or artificial materials added to soil to provide nutrients and improve plant growth
• The five kingdoms are Animals, Plants, Fungi, Prokaryotes and Protists
• Genetically modified organisms are organisms that have had their genome altered
• Genetic engineering is the modification of an organisms genome by the insertion of a desired gene from one organism to another, enabling beneficial characteristics
• Genome is the complete genetic material of an organism
• Ligase is an enzyme that joins the sticky ends of DNA together forming recombinant DNA
• Lucy is a 3.2 million year old female hominid fossil exhibiting more human traits then Ardi
• A mutation is a random change in the base sequence of DNA which can result in genetic variation
• Natural selection is the process where organisms that are better adapted to an environment survive and reproduce
• Recombinant DNA is a combination of DNA from two different organisms
• Restriction enzymes cut the DNA molecules at specific sequences creating sticky ends
• Selective breeding is the process in which humans artificially select organisms to breed and produce offspring with the chosen characteristics
• Sticky ends are the staggered cut formed by restriction enzymes in double-stranded DNA
• Tissue culture is a method of growing living tissue or cells in a suitable medium to produce clone plants
• Vectors are carriers used to transfer a gene from one organism to another
• Process of tissue culture-

  Choose a plant with desirable characteristic. Using tweezers, remove a piece of tissue from a fast-growing region of plant, often the root or shoot tip. Using an aseptic technique (sterile) place the tissue on a special growth medium with hormones and nutrients until it’s developed and can be transferred to compost for further growth
• Advantages of tissue culture-

  Produces offspring with desirable characteristics

  Can help preserve endangered species

  Increase the number of crops resistant to harmful weather conditions
• Disadvantages of tissue culture-

  Gene pool is reduced which decreases survival rate if diseases occur

  Low survival rate and genetic problems
• Process of genetic engineering-

  Genes from chromosomes are cut out using restriction enzymes. The same restriction enzyme is then used to cut up a vector, like a bacterial plasmid, where the genes will be placed. Ligase enzymes attach the sticky ends of the gene and vector together to produce a recombinant gene product. This is placed into an early stage organism where it will develop with the desired characteristics. In plants, it will be places into the meristems and produce a clone.
• Advantages of genetic engineering-

  Improving agricultures growth rates and intruding modifications which increase yields

  Produce mass hormones in microorganisms which are used for medicine
• Disadvantages of genetic engineering-

  Genetically modified plants are infertile and can spread into wild plants, affecting the entire environment

  The affects of genetically modified crops are unknown

  Pose a selection pressure
• Fertilisers provide useful nutrients (nitrates and phosphates)

  to plants which makes them more resistant to harmful environmental conditions and increases growth
• Advantages of selective breeding-

  Individual organisms can be bred to be resistant to a particular disease which can increase yield
• Disadvantages of selective breeding-

  Selecting for advantageous characteristics can cause health problems in the offspring

  Lack of genetic variation which leaves organisms vunerable to environmental pressures

  Ethical issues
• Process of Natural selection-

  G - genetic variation

  E - environment pressures

  N - natural selection

  I - inheritance

  E - evolution
• Process of selective breeding-

  G - genetic variation

  A - artificial selection

  B - breeding

  O - offspring

  R - repeat