OCR F215 5.2.1 cloning in plants
- Created by: aliza farrukh
- Created on: 02-05-10 18:43
a) outline the difference between reproductive and non-reproductive cloning
reproductive cloning =>production of a new individual with the same genotype of an existing one
non-reproductive cloning => supplies replacement cells whose genotype matches that of an existing organism
b) describe the production of natural clones in plants using the example of vegetative propagation in elm trees
clones => whole organism which carries identical genetic material because they are derived from the same original DNA
examples of natural cloning => identical twins, plants reproducing asexually, bacteria dividing by binary fission.
vegetative propagation =>production of structures in an organism that can grow into new organisms. contain same genetic information as the parent therefore clones of parents. form of natural cloning
natural vegetative propagation in elm tree
- elm tree are adapted to reproduce asexually following damage to parent plant
- allows species to survive catastrophes i.e. burning or disease
- new growth in the form of root suckers appear within 2 months after destruction of main trunk
- suckers grow from meristem tissue in trunk close to the ground since where least damage is likely to occur.
advantages
- root suckers help the elm spread because they can grown round the original trunk
- when tree is stressed (felled during the coppice cycle) suckers grow into a circle of new elms called clonal patch
- clonal patching puts out new suckers so that the patch keeps expanding as far the resources permit
disadvantages
- when new trees get to 10cm in diameter they become infected and die
- new trunks are clones of old ones so they have any resistance to the fungal attack therefore remain vulnerable
- no genetic variation within cloned population so natural selection cant occur
c) describe the production of artificial clones of plants from tissue culture
tissue culture => separation of cells of any tissue…
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