Cloning Flashcards
English elm reproduction.
Presence of meristem cells in trunk allows root suckers to grow,
Tree becomes damaged,
More root suckers grow,
Tree dies clonal patch is formed around tree.
Vegetative propagation
The production of a structure in an organism that can then grow into a new organism. The offspring are clones of the original organism.
What is a clonal patch?
A circle of genetically identical elms formed when the origional elm dies.
Advantages of vegetative proagation.
Does not require sexual reproduction,
It is fast,
All clones have the same desired features,
If original plant dies then clones will survive.
Disadvantages of vegetative propagation
No genetic variation, extremely susceptible to disease,
Disease spreads more easily,
Susceptible to environmental changes,
No natural selection
What is Tissue culture in plants?
Undifferentiated callus tissue grown in a nutrient medium containing plant hormones that stimulate the development of the whole plant.
Cauliflower cloning.
Remove some explant,
Sterilise in bleach and rinse in sterile water,
Place explant onto growth medium,cover,
After a few weeks remove some callus tissue and place in growth medium with hormones encouraging root and shoot growth,
After a few weeks transfer into compost.
Advantages of plant cloning in agriculture.
Can clone high value plants,
Disease free,
You know exactly what the crop will be like.
Disadvantages of plant cloning in agriculture.
Ethical problems, Expensive, No variation, More susceptible to disease, May produce sterile offspring.
Why clone animals?
High value agricultural animals,
Racehorses,
Endangered species,
Animals modified for pharming.
Splitting embryos steps.
Chose male and female and harvest sex cells from both,
Carry out in vitro fertilisation,
Zygote divides to the 16 cell stage and is then split into segments,
Each embryo is implanted directly into surrogate mother,
Healthy foetuses are delivered at full term Abnormal ones are aborted.
Nuclear transfer method.
Remove somatic cell (Remove nucleus),
Remove egg cell (Remove nucleus),
Put nucleus from somatic cell in egg cell,
Stimulate fertilisation using electricity,
Implant in Intermediate mother with tied oviducts,
Remove early embryo and implant into surrogate mother,
Deliver at full term.
Therapeutic cloning.
The use of cloned cells to generate cells, tissues, organs to replace damaged ones.
Advantages of therapeutic cloning.
Cells identical to treated person, no rejection,
May eliminate the problem of organ shortages,
Cloned cells are totipotent (can produce any body cell needed)
Use of cloned cells eliminates need for dangerous whole organ transplants.
Therapeutic cloning issues.
Ethical issues (requires the formation and destruction of embryos). There is a lack of understanding of how cloned cells behave over time.
