Adaptations

• Genetic engineering


  The process of modifying the genome of an organism by cutting out genes from one organism and transferring them to cells of a different organism
• Genetic engineering


  1. Identify the gene to transfer

  2. Use enzymes to isolate the gene

  3. Transfer the gene into a plasmid or virus (vector)

  4. Transfer the vector into the cells of the target organism
• Genetic engineering in medicine

  • Used to produce human insulin in bacteria for treating type 1 diabetes
• Genetic engineering in agriculture

  • Used to create genetically modified (GM) crops that have higher yields, resistance to disease/insects, or tolerance to herbicides
• Spraying herbicides on GM crops

  Does not harm the GM crop
• Some people question the safety of GM crops, such as potential harm to insects or wildflowers, and want more research on health effects
• Gene therapy


  The use of genetic engineering to treat inherited disorders in humans
• The long-term effects of gene therapy are not known, such as the potential effects on other genes
• Genetic engineering is done at an early stage of an organism's development, such as the embryo stage, to ensure all cells receive the transferred gene
• Cloning


  Producing genetically identical organisms
• Humans have been cloning plants for many years
• Advantage of cloning plants

  • The clone is genetically identical to the original plant, so we know exactly what the clone's characteristics will be
  • Offspring from sexual reproduction would be different
• Cloning plants by cuttings

  1. Take a small piece of the plant

  2. Dip the end in rooting powder (contains plant hormones)

  3. Roots develop, producing a genetically identical clone
• Tissue culture


  Taking a plant, dividing it into hundreds of tiny pieces, each with a small number of cells, and incubating them with plant hormones to stimulate growth into fully grown clones
• Tissue culture conditions must be sterile to avoid introducing microorganisms like bacteria or fungi
• Advantages of tissue culture

  • Allows growers to produce thousands of genetically identical plants quickly and cheaply
  • Gardeners can be certain of getting the desired characteristics, like flower colour
• Tissue culture is also used to preserve rare plant species
• Cloning by embryo transplants

  Fertilization produces a fertilized egg, which is allowed to develop into an early stage embryo. The embryo is then split into two and transplanted into host mothers, resulting in two identical offspring (clones).
• Cloning by embryo transplants

  • Requires sperm and egg cell from animals with desired characteristics
  • Cells in the embryo must not have started to specialize
• Cloning by embryo transplants has the problem that the offspring may not have the desired characteristics
• Adult cell cloning


  Involves removing a cell from the animal to be cloned, removing the nucleus, inserting it into an unfertilized egg cell with the nucleus removed, and stimulating the egg cell to divide and form an embryo. The embryo is then inserted into the womb of an adult female to continue development.
• Adult cell cloning


  • Clones have the same genetic information as the original adult cell
  • The clone looks nothing like the host mother as it contains none of her genetic material
• The key benefit of adult cell cloning is that the characteristics of the clone are known, as it is cloned from an adult
• Three domain classification system

  • Archaea (primitive bacteria found in extreme conditions)
  • Bacteria (true bacteria like those in the human digestive system)
  • Eukaryota (animals, plants, fungi, protists like amoeba)
• Using evolutionary trees to show relationships between organisms

  1. Classify living organisms based on data like DNA

  2. Use fossils to classify extinct organisms (but fossil record is often incomplete)
• Linnaeus divided all living organisms into two kingdoms: animal kingdom and plant kingdom
• Linnaeus' classification categories


  • Kingdom
  • Phylum
  • Class
  • Order
  • Family
  • Genus
  • Species
• Mnemonic for Linnaeus' classification categories: "King Phillip came over for good soup"
• Binomial name


  Genus and species name for an organism
• Binomial name examples


  • Equus quagga (zebra)
  • Ursus maritimus (polar bear)
• Linnaeus' classification system is based on observable characteristics, but modern biology uses more advanced techniques like microscopes and DNA analysis