Variation and evolution-B14

• What do mutations do? They can change the sequence of bases in a gene, which can change the amino acid sequence
• what does an advantageous allele allow for ?

  survival and reproduction
• When are two populations no longer the same species ?

  when they can’t produce fertile offspring
• What do people selectively breed for ?

  Desired traits.

  examples:

  disease , drought resistance

  higher yield of crops/meat/milk

  domestic animals with general natures

  bright coloured flowers
• What does selective breeding to the the number of alleles present in a population ?

  Reduces the amount of alleles so less variation
• What does less variation lead to?

  Less variation leads to higher chances of being wiped out by new diseases/predators
• Give some examples of environmental variation:

  • scars
  • piercings
  • dyed hair
  • hair length
• Give some examples of both genetic and environmental variation:

  • weight
  • height
  • skin colour
• Describe the process of selective breeding

  • select individuals with desired characteristics
  • breed together
  • select offspring with most desirable characteristics
  • breed together
  • repeat over several generations
• Describe adult cell cloning

  • nucleus removed from current organism
  • inserted into excel from different individual with its nucleus removed
  • Electric shock to stimulate growth
  • Cell divides into embryo
  • implanted into uterus of surrogate Mother
• Describe embryo cloning

  • collect embryo of top quality animal
  • Divide embryo into individual cells
  • Each salary grows into separate embryo
  • Cloned embryos transferred to surrogate mothers
  • born - genetically identical
• What are some advantages of adult cell cloning?

  • can save a species from extinction.
  • Don’t need to genetic modification or selective breeding easy to keep desired characteristics.
• What are some disadvantages of adult cell cloning?

  • If there is a disease all the clones will be wiped out
  • moral ethics
  • no variation
• What are some advantages of embryo cloning?

  • good, livestock can reproduce more offspring in a lifetime
  • cloned embryos are easy to transport
• What are some disadvantages of embryo cloning?

  • Clothes will be wiped out if there’s a new disease due to no variation
• Describe genetic engineering

  • Gene cut out using enzymes
  • Inserted into genetic material of modified organisms, using a vector at early stage of development
  • Organism will show characteristics
• what are some concerns of genetic engineering?

  Could have negative impacts on food web,

  could be harmful to humans

  could outcompete native species of plant