Cloning + biotechnology

• Somatic cell nuclear transfer


  Taking the nucleus from an adult somatic cell with a desired trait, removing the nucleus from an egg cell, and inserting the somatic cell nucleus into the enucleated egg to create a pluripotent blastocyst to implant into a surrogate mother
• Arguments for cloning


  • Desirable characteristics always passed on
  • Faster process
  • Avoid mating risks
• Arguments against cloning


  • Can be expensive
  • No genetic variability
  • More susceptible to disease
  • Shorter lifespans
  • Poor success rate
• Immobilized enzymes


  Enzymes attached to an insoluble medium or material, so they are not mixed up in with the products and can be easily separated out
• Encapsulation


  1. Enzyme trapped inside a semi-permeable membrane

  2. Substrate can still get in and bind to the active site

  3. Enzyme breaks down substrate into products

  4. Products are released
• Entrapment


  1. Enzyme trapped inside silica gel

  2. Substrate can still get in and bind to the active site

  3. Enzyme breaks down substrate into products

  4. Products are released
• Cross-linking


  Covalent or ionic bonds formed between the amino acids in the enzyme
• Carrier bound


  1. Enzyme attached to a carrier such as activated carbon or agarose

  2. Keeps the enzyme in place so it can't be mixed in with the final product
• Advantages of immobilized enzymes


  • Enzyme can be easily removed to be used again
  • Less downstream in processing
  • Less enzyme needed to be extracted from products
  • More stable (last longer, resistant to changes in pH, temperature)
• Disadvantages of immobilized enzymes


  • Immobilization process can reduce enzyme activity
  • Higher initial cost compared to free enzymes
  • More complex procedure involved
• How to Make clones from plant cuttings?


  1. Use a healthy shoot
  2. Cut stem at a slant (Large SA), between nodes (where leaves begin to grow)
  3. Dip the stem in rooting powder
  4. Place in soil and add water
  5. Cover with plastic bag, to reduce transpiration
• Advantages of cloning?

  1. Can clone seedless fruit
  2. Cheap
  3. Clones have desired characteristics (genetic makeup)
• Disadvantages of cloning?


  Low genetic diversity
• Micropropagation


  Using tissue culture to grow plants from a cell-based medium
• Tissue culture process


  1. Sterilize area and equipment

  2. Cut plant material into explants

  3. Sterilize explants

  4. Place explants onto agar medium

  5. Induce cell division and callus formation

  6. Treat callus to induce roots or change development (By auxins/cytokines)

  7. Plant plantlet into soil and greenhouse
• Explants


  • Leaf, root or bud sections from parent plant
• Agar medium


  Contains glucose for respiration and amino acids to make proteins
• Callus


  Mass of undifferentiated plant cells that forms
• Callus treatment


  1. Induce roots by high auxin or cytokines

  2. Change plant hormone ratio to alter callus development
• What are primary metabolites?


  Molecules needed for normal function
• What are secondary metabolites?


  (products) Not part of normal growth