Cloning Grade 10 EST
Reproduction • Sexual (principles of heredity) • Asexual (clones) • Cloning is the reproduction of an individual, part of that individual or one of its genes in order to obtain an exact copy.
Natural Cloning • Natural cloning produces genetically identical individuals through asexual reproduction.
Budding – in this form of reproduction, a new individual develops from a protusion that eventually detaches itself from the parent.
Layering – in this form of reproduction, which is specific to plants, roots – called stolons – develop from a branch in contact with the ground.
Propagation by cutting – in this form of reproduction, also specific to plants, a new individual is formed from a separated section of the plant (not seeds), which falls to the ground.
Artificial Plant Cloning • Artificial plant cloning involves humans. • See illustration p. 371.
Animal Cloning In mammals: • Remove cell from individual to be cloned • Remove nucleus of ovum from another • Combine cell and ovum = embryo • Implant in surrogate mother
Human Cloning • Reproductive cloning is the application of cloning techniques to obtain a new individual genetically identical to the one being cloned. • Therapeutic cloning is the application of cloning techniques to obtain tissues or organs genetically identical to those of a person in need of a transplant or medical grafting.
Molecular Cloning • Production of multiple copies of the same gene. • Useful in case of an accident or genetic defect.