Cloning Flashcards
Define cloning
- the process leading to the formation of clone
Define clones
- GENETICALLY IDENTICAL copies of an organism
What process can cloning of cells be referred to
- mitosis
What process can cloning of whole organisms be referred to
- asexual reproduction
What are the 3 advantages of natural cloning
1) same environment suitable for parent and offspring
2) rapid
3) reproduction doesn’t require two parents or sexual reproduction
What are the 3 disadvantages of natural cloning
1) offspring overcrowding
2) no genetic variation
3) selection is impossible
4) entire population vulnerable to environmental changes
What is natural vegetative propagation
- generation of multiple offspring from one pant without sexual reproduction through the vegetative parts of the plant (non reproductive)
What is an advantage of natural vegetative propagation
- only one parent is required
- saves resources
What is a disadvantage of natural vegetative propagation
- one disease can affect the whole population
What is the process of natural vegetative propagation
1) many plants can reproduce asexually following
2) root sucker, or basal sprouts, appear within 2 months
3) these grow from meristem tissue, where damage is least likely to have occurred
4) the offspring are genetically identical to the parent plant
What are runners & stolen
- horizontal stems lying on the ground that can from roots
What are rhizomes
- horizontal underground stems lying on the ground that can be form roots and shoots
What are suckers
- new stems arising form the roots of plants
What are bulbs
- underground swollen stem with stored food and a bud
What are corms
- underground stem with scaly leaves and buds
What are tubers
- under ground stem e.g. potatoes
What are leaf margins
- new leaves that bud off existing leaves
What are artificial micropropagation and tissue culture
- the use of plant cuttings to produce clones
- process produces many genetically identical plants from just one plant, e.g. Elm trees
What is the process of artificial micropropagation and tissue culture
1) cells are taken from shoot tip with sterile forceps
2) these are explants
3) explants placed in nutrient agar
4) cells proliferate to form a big ball of cells, called a callus
5) cells are treated with shoot stimulating hormones
6) cells grow into plantlets
7) treated with root-stimulating hormones
8) plants grow
9) plants are planted into compost
What are the advantages of artificial micropropagation and tissue culture
- farmers know what the crop will be like
- reduced costs= as all the crop is ready for harvest at the same time
- all crop has ideal features
- faster than selective breeding
- horticulture (small scale) and agriculture (large scale)
What is the disadvantage of micropropagation and tissue culture
- all plants are susceptible to the same pest or disease
Why does natural cloning not happen as frequently in animals as it does in plants
- because most animals reproduce sexually creating genetic variation and diversity
What are the few exceptions to natural clones in animals
1) Identical twins
2) D. pulex and A. pisum
How do identical twins come about
- the zygote divides early in development to form 2 separate cells
- each cell is genetically identical and grows into an individual organism
What are D. pulex and A. pisum
- species which reproduce asexually to produce clones
How many ways can you make artificial clones in animals
2
What are the 2 ways you make artificial clones in animals
1) Somatic cell nuclear transfer (SCNT)
2) Embryo twinning (splitting)
