Manipulating Genes

• What is selective breeding also known as?

  Artificial selection
• What have humans been using selective breeding for?

  To produce food crops and domesticated animals
• What is the main purpose of selective breeding?

  To breed plants and animals with desirable traits
• What are the steps involved in selective breeding?

  1. Choose parents with desired characteristics
  2. Breed them together
  3. Select offspring with desired traits and breed
  4. Repeat over many generations
• What types of characteristics can be selected in selective breeding?

  Disease resistance, meat or milk production, temperament
• What is a potential negative consequence of selective breeding?

  It can lead to interbreeding and inherited defects
• What is one characteristic that could be selected in food crops?

  Disease resistance
• What is one characteristic that could be selected in domesticated animals?

  Higher meat or milk production
• What is a desirable trait in domestic dogs that can be selected?

  Gentle nature
• How does interbreeding affect certain breeds?

  It makes them prone to diseases and defects
• Key Point

  Owners have to be very careful when mating pedigree dogs to make sure that they are not too closely related. Pedigree dogs are more likely to get diseases or have inherited defects
• Key Point

  Genetic engineering is a good example of a new technology that could be very useful. However, there are ethical issues to consider
• What is genetic engineering?

  A method to change organisms' characteristics
• How does genetic engineering change an organism?

  By introducing a gene from another organism
• What are the steps involved in genetic engineering?

  1. Use enzymes to isolate the required gene
  2. Insert the gene into a vector (e.g., plasmid or virus)
  3. Use the vector to insert the gene into target cells
• Why is using a vector efficient in genetic engineering?

  Because the vector can replicate itself
• What happens if genes are inserted at the egg or embryo stage?

  All cells will receive the new gene
• What are some benefits of genetically engineered plant crops?

  • Resistance to diseases, insects, or herbicides
  • Production of bigger, better fruits
• What are genetically modified crops also known as?

  GM crops
• What concerns do people have about GM crops?

  Possible long-term effects on wild flowers and health
• How is genetic modification being explored in medical research?

  To overcome serious inherited disorders
• What useful substances can genetically engineered fungi or bacteria produce?

  Human insulin for Type 1 diabetes
• What future possibilities does genetic modification hold for humans?

  To cure or prevent inherited diseases