cloning

• what is a clone?

  • a genetically identical organism
• what is micropropagation?

  • pant with desirable characteristics chosen to be cloned - explants taken from tip of stem to side of shoots
  • explants sterilised to kill microorganisms
  • explants grow in vitro - placed in petri dish contains nutrient medium - medium has all nutrients explant needs to grow - contains growth hormones
  • cell in explant grow and divide into smaller plant
  • small plants taken out of medium - planted in soil - put into greenhouses - develop into plants genetically identical to original plant - share same characteristics
• dolly the sheep?

  • nucleus of sheep egg cell was removed - create enucleated cell
  • diploid nucleus inserted in place - nucleus from mature udder of different cell of different sheep
  • cell stimulated so started dividing by mitosis like normal fertilised egg
  • dividing cell implanted into uterus of other sheep to develop until birth
  • result was dolly a clone of sheep that the udder cell came from.
• how do transgenic animals produce human proteins?

  • cows and sheep make protein naturally from their milk - transfer human genes into cells of these animals - produce useful human proteins in their milk
  • can produce human antibodies - used in therapy for illnesses like arthuritis ~