- Created by: Rebecca
- Created on: 21-06-11 13:06
- Clones are asexually reproduced, hence genetically identical.
- Cloning can occue natural, for exmaple in bacteria, yeast, and plants grown from suckers, bulbs and corms.
- Artificial clones can be formed in animals by separating embryos at an early stage.
- Artificial plant clones can be formed by taking cuttings and performing micropropagation.
Cloning Animals- Embryo Cloning:
- This technique has been used to produce genetically identical individuals, and has made it possibly for farmers to dramatically increase the number of animals.
- Eggs are taken from high milk yielding cows and are fertilised in a petri dish using sperm from the best bulls.
- This is known as in vitro fertilisation (IVF or Test-Tube Fertilisation).
- The fertilised egg divides to form a ball of cells.
- This group of cells or young embryo are split into separate cells. Each of these cells then develop into a new embryo, genetically identical to the original.
- The embryos are then transplanted into other cows called surrogates.
- As well as increasing the farmer's stock, this technique is also used to preserve rare breeds where the embryo of the rare breed is split and transplanted into a surrogate common breed.
Cloning Animals- Cloning by Nuclear Transplants:
- This technique allows clones to be produced from one individual.
- It involves transplanting a nucleus from a somatic cell into an egg cell.
- Cells are taken from the tissues of the udder of a sheep (the donor) and cultured in a medium which stops division.
- An unfertilised egg is removed from a different sheep (the recipient) and the nucleus is removed leaving an egg cell without a nucleus.
- The donor and recipient cells are fused together and allowed to divide producing a ball of cells.
- The developing embryo is implanted into the uterus of another sheep (the host or surrogate).
- The lamb born is genetically identical to the original donor sheep.
- This technique has enabled desirable qualities to be preserved for future generations.
- Cloning means that if, for example, a mutation occurs in a cow that means she yields much more milk than the rest of her herd, she can be cloned, as this is the only technique that…