8.3

• What is the process of cloning in plants using tissue cultures?

  Many identical copies can be made from a small sample.
• Which plants are commonly cloned using tissue cultures?

  Orchids, callistemons, and eucalypts.
• Why is the Wollemi pine significant in plant cloning?

  It is a very rare plant that can be cloned.
• What are the advantages of plant tissue culture?

  • Slow growing plants can be produced in large numbers
  • Plants can be cultured all year round
  • Virus-free tissue can be produced (e.g., Panama disease-free banana)
  • Cultured plants can be transported from country to country
• What are the two main methods of artificial cloning in mammals?

  Cloning using embryo splitting and somatic cell nuclear transfer.
• What is embryo splitting in cloning?

  • Process of separating the totipotent cells of a very early embryo
  • Resultant cells are each able to form a new embryo
• What is somatic cell nuclear transfer?

  • Cloning technique involving the transfer of the nucleus of a somatic cell
  • The nucleus is transferred into the cytoplasm of an enucleated cell
  • The enucleated cell is then stimulated to divide
• What are the advantages of cloning?

  • Desirable traits are continued
  • Use of IVF techniques and surrogacy allows scientists to have control
  • Common techniques used in the livestock industry
  • Can also be used in conservation
• What are the disadvantages of cloning?

  • Creation of monocultures
  • Reduction in genetic diversity
  • Low success rate of somatic cell nuclear transfer (SCNT)
  • Dolly was the only live birth from 277 clones
  • Snuppy was the only live dog out of 123 surgically implanted
  • Today, 10% of clones survive beyond birth
  • High abnormality rate
  • Premature death is common